global: Convert simple_strtoul() with hex to hextoul()

It is a pain to have to specify the value 16 in each call. Add a new
hextoul() function and update the code to use it.

Add a proper comment to simple_strtoul() while we are here.

Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/net/e1000_spi.c b/drivers/net/e1000_spi.c
index 4fcc65d..69adf28 100644
--- a/drivers/net/e1000_spi.c
+++ b/drivers/net/e1000_spi.c
@@ -399,7 +399,7 @@
 	}
 
 	/* Parse the arguments */
-	dest = (void *)simple_strtoul(argv[0], NULL, 16);
+	dest = (void *)hextoul(argv[0], NULL);
 	offset = simple_strtoul(argv[1], NULL, 0);
 	length = simple_strtoul(argv[2], NULL, 0);
 
@@ -444,7 +444,7 @@
 	}
 
 	/* Parse the arguments */
-	source = (const void *)simple_strtoul(argv[0], NULL, 16);
+	source = (const void *)hextoul(argv[0], NULL);
 	offset = simple_strtoul(argv[1], NULL, 0);
 	length = simple_strtoul(argv[2], NULL, 0);
 
diff --git a/drivers/net/fm/fdt.c b/drivers/net/fm/fdt.c
index 242d27a..3855d7d 100644
--- a/drivers/net/fm/fdt.c
+++ b/drivers/net/fm/fdt.c
@@ -42,7 +42,7 @@
 	if (!p)
 		return;
 
-	fmanfw = (struct qe_firmware *)simple_strtoul(p, NULL, 16);
+	fmanfw = (struct qe_firmware *)hextoul(p, NULL);
 	if (!fmanfw)
 		return;
 
diff --git a/drivers/net/fsl-mc/mc.c b/drivers/net/fsl-mc/mc.c
index 914ec00..3712221 100644
--- a/drivers/net/fsl-mc/mc.c
+++ b/drivers/net/fsl-mc/mc.c
@@ -956,8 +956,7 @@
 	char *dram_block_size_env_var = env_get(MC_MEM_SIZE_ENV_VAR);
 
 	if (dram_block_size_env_var) {
-		dram_block_size = simple_strtoul(dram_block_size_env_var, NULL,
-						 16);
+		dram_block_size = hextoul(dram_block_size_env_var, NULL);
 
 		if (dram_block_size < CONFIG_SYS_LS_MC_DRAM_BLOCK_MIN_SIZE) {
 			printf("fsl-mc: WARNING: Invalid value for \'"
diff --git a/drivers/net/pfe_eth/pfe_cmd.c b/drivers/net/pfe_eth/pfe_cmd.c
index 364750f..2fe0db0 100644
--- a/drivers/net/pfe_eth/pfe_cmd.c
+++ b/drivers/net/pfe_eth/pfe_cmd.c
@@ -41,7 +41,7 @@
 			}
 
 			id = simple_strtoul(argv[4], NULL, 0);
-			addr = simple_strtoul(argv[5], NULL, 16);
+			addr = hextoul(argv[5], NULL);
 			size = 4;
 
 			for (i = 0; i < num; i++, addr += 4) {
@@ -75,7 +75,7 @@
 			}
 
 			id = simple_strtoul(argv[4], NULL, 0);
-			addr = simple_strtoul(argv[5], NULL, 16);
+			addr = hextoul(argv[5], NULL);
 			size = 4;
 
 			for (i = 0; i < num; i++, addr += 4) {
@@ -99,9 +99,9 @@
 			}
 
 			id = simple_strtoul(argv[4], NULL, 0);
-			val = simple_strtoul(argv[5], NULL, 16);
+			val = hextoul(argv[5], NULL);
 			val = cpu_to_be32(val);
-			addr = simple_strtoul(argv[6], NULL, 16);
+			addr = hextoul(argv[6], NULL);
 			size = 4;
 			pe_dmem_write(id, val, addr, size);
 		} else {
@@ -123,7 +123,7 @@
 				return;
 			}
 
-			offset = simple_strtoul(argv[4], NULL, 16);
+			offset = hextoul(argv[4], NULL);
 
 			for (i = 0; i < num; i++, offset += 4) {
 				pe_lmem_read(&val, 4, offset);
@@ -141,9 +141,9 @@
 				return;
 			}
 
-			val = simple_strtoul(argv[4], NULL, 16);
+			val = hextoul(argv[4], NULL);
 			val = cpu_to_be32(val);
-			offset = simple_strtoul(argv[5], NULL, 16);
+			offset = hextoul(argv[5], NULL);
 			pe_lmem_write(&val, 4, offset);
 		} else {
 			printf("Usage: pfe pe lmem [read | write] <parameters>\n");
diff --git a/drivers/net/phy/b53.c b/drivers/net/phy/b53.c
index 21da53c..695fac4 100644
--- a/drivers/net/phy/b53.c
+++ b/drivers/net/phy/b53.c
@@ -646,8 +646,8 @@
 		return ret;
 	}
 
-	page = simple_strtoul(argv[1], NULL, 16);
-	offset = simple_strtoul(argv[2], NULL, 16);
+	page = hextoul(argv[1], NULL);
+	offset = hextoul(argv[2], NULL);
 	width = simple_strtoul(argv[3], NULL, 10);
 
 	switch (width) {
@@ -698,13 +698,13 @@
 		return ret;
 	}
 
-	page = simple_strtoul(argv[1], NULL, 16);
-	offset = simple_strtoul(argv[2], NULL, 16);
+	page = hextoul(argv[1], NULL);
+	offset = hextoul(argv[2], NULL);
 	width = simple_strtoul(argv[3], NULL, 10);
 	if (width == 48 || width == 64)
 		value64 = simple_strtoull(argv[4], NULL, 16);
 	else
-		value = simple_strtoul(argv[4], NULL, 16);
+		value = hextoul(argv[4], NULL);
 
 	switch (width) {
 	case 8:
diff --git a/drivers/net/phy/mv88e6352.c b/drivers/net/phy/mv88e6352.c
index 62a7f19..07a8e50 100644
--- a/drivers/net/phy/mv88e6352.c
+++ b/drivers/net/phy/mv88e6352.c
@@ -256,7 +256,7 @@
 	phyaddr = simple_strtoul(argv[1], NULL, 10);
 	port = simple_strtoul(argv[2], NULL, 10);
 	reg = simple_strtoul(argv[3], NULL, 10);
-	value = simple_strtoul(argv[4], NULL, 16);
+	value = hextoul(argv[4], NULL);
 
 	ret = sw_reg_write(name, phyaddr, port, reg, value);