GPIO: pca953x: Remove compilation warnings on arm64

Warnings:
w+../drivers/gpio/pca953x.c: In function ‘do_pca953x’:
w+../drivers/gpio/pca953x.c:220:5: warning: cast from pointer to integer
of different size [-Wpointer-to-int-cast]
w+../drivers/gpio/pca953x.c:233:10: warning: cast from pointer to
integer of different size [-Wpointer-to-int-cast]

Signed-off-by: Michal Simek <michal.simek@xilinx.com>
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index 932dfe9..238e028 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -217,7 +217,7 @@
 
 	/* All commands but "device" require 'maxargs' arguments */
 	if (!c || !((argc == (c->maxargs)) ||
-		(((int)c->cmd == PCA953X_CMD_DEVICE) &&
+		(((long)c->cmd == PCA953X_CMD_DEVICE) &&
 		 (argc == (c->maxargs - 1))))) {
 		return CMD_RET_USAGE;
 	}
@@ -230,7 +230,7 @@
 	if (argc > 3)
 		ul_arg3 = simple_strtoul(argv[3], NULL, 16) & 0x1;
 
-	switch ((int)c->cmd) {
+	switch ((long)c->cmd) {
 #ifdef CONFIG_CMD_PCA953X_INFO
 	case PCA953X_CMD_INFO:
 		ret = pca953x_info(chip);