global: Migrate CONFIG_SET_DFU_ALT_BUF_LEN to CFG

Perform a simple rename of CONFIG_SET_DFU_ALT_BUF_LEN to CFG_SET_DFU_ALT_BUF_LEN

Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/board/samsung/common/misc.c b/board/samsung/common/misc.c
index 9c0ec29..5ffa216 100644
--- a/board/samsung/common/misc.c
+++ b/board/samsung/common/misc.c
@@ -41,7 +41,7 @@
 #ifdef CONFIG_SET_DFU_ALT_INFO
 void set_dfu_alt_info(char *interface, char *devstr)
 {
-	size_t buf_size = CONFIG_SET_DFU_ALT_BUF_LEN;
+	size_t buf_size = CFG_SET_DFU_ALT_BUF_LEN;
 	ALLOC_CACHE_ALIGN_BUFFER(char, buf, buf_size);
 	char *alt_info = "Settings not found!";
 	char *status = "error!\n";