env: Rename nand env_location to nand_env_location

We want to use this name for all environment drivers. Update the nand
driver to use a more specific name.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Tom Rini <trini@konsulko.com>
diff --git a/env/nand.c b/env/nand.c
index 90f274b..d1b8b26 100644
--- a/env/nand.c
+++ b/env/nand.c
@@ -158,12 +158,12 @@
 	return 0;
 }
 
-struct env_location {
+struct nand_env_location {
 	const char *name;
 	const nand_erase_options_t erase_opts;
 };
 
-static int erase_and_write_env(const struct env_location *location,
+static int erase_and_write_env(const struct nand_env_location *location,
 		u_char *env_new)
 {
 	struct mtd_info *mtd;
@@ -189,7 +189,7 @@
 	int	ret = 0;
 	ALLOC_CACHE_ALIGN_BUFFER(env_t, env_new, 1);
 	int	env_idx = 0;
-	static const struct env_location location[] = {
+	static const struct nand_env_location location[] = {
 		{
 			.name = "NAND",
 			.erase_opts = {