env: Rename getenv/_f() to env_get()

We are now using an env_ prefix for environment functions. Rename these
two functions for consistency. Also add function comments in common.h.

Quite a few places use getenv() in a condition context, provoking a
warning from checkpatch. These are fixed up in this patch also.

Suggested-by: Wolfgang Denk <wd@denx.de>
Signed-off-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/net/fec_mxc.c b/drivers/net/fec_mxc.c
index 424c347..797e34f 100644
--- a/drivers/net/fec_mxc.c
+++ b/drivers/net/fec_mxc.c
@@ -1096,7 +1096,7 @@
 			sprintf(mac, "eth%daddr", fec->dev_id);
 		else
 			strcpy(mac, "ethaddr");
-		if (!getenv(mac))
+		if (!env_get(mac))
 			eth_env_set_enetaddr(mac, ethaddr);
 	}
 	return ret;
diff --git a/drivers/net/fm/b4860.c b/drivers/net/fm/b4860.c
index 5aeeb87..3245bee 100644
--- a/drivers/net/fm/b4860.c
+++ b/drivers/net/fm/b4860.c
@@ -97,7 +97,7 @@
 			 * Extract hwconfig from environment since environment
 			 * is not setup yet
 			 */
-			getenv_f("hwconfig", buffer, sizeof(buffer));
+			env_get_f("hwconfig", buffer, sizeof(buffer));
 			buf = buffer;
 
 			/* check if XFI interface enable in hwconfig for 10g */
diff --git a/drivers/net/fm/fdt.c b/drivers/net/fm/fdt.c
index 9918d80..5920fec 100644
--- a/drivers/net/fm/fdt.c
+++ b/drivers/net/fm/fdt.c
@@ -36,7 +36,7 @@
 		return;
 
 	/* If the environment variable is not set, then exit silently */
-	p = getenv("fman_ucode");
+	p = env_get("fman_ucode");
 	if (!p)
 		return;
 
diff --git a/drivers/net/fsl-mc/mc.c b/drivers/net/fsl-mc/mc.c
index 3a30c03..be82371 100644
--- a/drivers/net/fsl-mc/mc.c
+++ b/drivers/net/fsl-mc/mc.c
@@ -530,7 +530,7 @@
 {
 	unsigned long timeout_ms = CONFIG_SYS_LS_MC_BOOT_TIMEOUT_MS;
 
-	char *timeout_ms_env_var = getenv(MC_BOOT_TIMEOUT_ENV_VAR);
+	char *timeout_ms_env_var = env_get(MC_BOOT_TIMEOUT_ENV_VAR);
 
 	if (timeout_ms_env_var) {
 		timeout_ms = simple_strtoul(timeout_ms_env_var, NULL, 10);
@@ -815,7 +815,7 @@
 {
 	unsigned long dram_block_size = CONFIG_SYS_LS_MC_DRAM_BLOCK_MIN_SIZE;
 
-	char *dram_block_size_env_var = getenv(MC_MEM_SIZE_ENV_VAR);
+	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,
@@ -1518,7 +1518,7 @@
 	 * address info properly. Without MAC addresses, the MC code
 	 * can not properly initialize the DPC.
 	 */
-	mc_boot_env_var = getenv(MC_BOOT_ENV_VAR);
+	mc_boot_env_var = env_get(MC_BOOT_ENV_VAR);
 	if (mc_boot_env_var)
 		run_command_list(mc_boot_env_var, -1, 0);
 #endif /* CONFIG_FSL_MC_ENET */
diff --git a/drivers/net/netconsole.c b/drivers/net/netconsole.c
index 3500047..2210c57 100644
--- a/drivers/net/netconsole.c
+++ b/drivers/net/netconsole.c
@@ -82,11 +82,11 @@
 
 	/* update only when the environment has changed */
 	if (env_changed_id != env_id) {
-		if (getenv("ncip")) {
+		if (env_get("ncip")) {
 			nc_ip = getenv_ip("ncip");
 			if (!nc_ip.s_addr)
 				return -1;	/* ncip is 0.0.0.0 */
-			p = strchr(getenv("ncip"), ':');
+			p = strchr(env_get("ncip"), ':');
 			if (p != NULL) {
 				nc_out_port = simple_strtoul(p + 1, NULL, 10);
 				nc_in_port = nc_out_port;
@@ -95,10 +95,10 @@
 			nc_ip.s_addr = ~0; /* ncip is not set, so broadcast */
 		}
 
-		p = getenv("ncoutport");
+		p = env_get("ncoutport");
 		if (p != NULL)
 			nc_out_port = simple_strtoul(p, NULL, 10);
-		p = getenv("ncinport");
+		p = env_get("ncinport");
 		if (p != NULL)
 			nc_in_port = simple_strtoul(p, NULL, 10);
 
diff --git a/drivers/net/phy/micrel_ksz90x1.c b/drivers/net/phy/micrel_ksz90x1.c
index 20f8a55..0bb99e6 100644
--- a/drivers/net/phy/micrel_ksz90x1.c
+++ b/drivers/net/phy/micrel_ksz90x1.c
@@ -258,7 +258,7 @@
 	if (ret)
 		return ret;
 
-	if (getenv("disable_giga"))
+	if (env_get("disable_giga"))
 		features &= ~(SUPPORTED_1000baseT_Half |
 		SUPPORTED_1000baseT_Full);
 	/* force master mode for 1000BaseT due to chip errata */
@@ -344,7 +344,7 @@
 		return ret;
 
 	/* add an option to disable the gigabit feature of this PHY */
-	if (getenv("disable_giga")) {
+	if (env_get("disable_giga")) {
 		unsigned features;
 		unsigned bmcr;