constify default env

I can't see any obvious needs for the default environment to be writable,
so make it const.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>

common/env_common.c

@@ -47,7 +47,7 @@ static uchar env_get_char_init (int index);
 #define XMK_STR(x)	#x
 #define MK_STR(x)	XMK_STR(x)
 
-uchar default_environment[] = {
+const uchar default_environment[] = {
 #ifdef	CONFIG_BOOTARGS
 	"bootargs="	CONFIG_BOOTARGS			"\0"
 #endif
@@ -162,7 +162,7 @@ uchar env_get_char (int index)
 	return (c);
 }
 
-uchar *env_get_addr (int index)
+const uchar *env_get_addr (int index)
 {
 	if (gd->env_valid)
 		return (uchar *)(gd->env_addr + index);

common/env_flash.c

@@ -74,7 +74,7 @@ static env_t *flash_addr_new = (env_t *)CONFIG_ENV_ADDR_REDUND;
 static ulong end_addr_new = CONFIG_ENV_ADDR_REDUND + CONFIG_ENV_SECT_SIZE - 1;
 #endif /* CONFIG_ENV_ADDR_REDUND */
 
-extern uchar default_environment[];
+extern const uchar default_environment[];
 
 
 uchar env_get_char_spec(int index)

include/environment.h

@@ -160,7 +160,7 @@ extern struct hsearch_data env_htab;
 unsigned char env_get_char (int);
 
 /* Function that returns a pointer to a value from the environment */
-unsigned char *env_get_addr(int);
+const unsigned char *env_get_addr(int);
 unsigned char env_get_char_memory (int index);
 
 /* Function that updates CRC of the enironment */