cmd: improve string matching for hex

Match the "=0x" instead of just "=0".

Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Heinrich.Schuchardt <xypron.glpk@gmx.de>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/cmd/nvedit_efi.c b/cmd/nvedit_efi.c
index 24944ab..7a30b5c 100644
--- a/cmd/nvedit_efi.c
+++ b/cmd/nvedit_efi.c
@@ -262,7 +262,7 @@
 	char *tmp_buf = NULL, *new_buf = NULL, *value;
 	unsigned long len = 0;
 
-	if (!strncmp(data, "=0x", 2)) { /* hexadecimal number */
+	if (!strncmp(data, "=0x", 3)) { /* hexadecimal number */
 		union {
 			u8 u8;
 			u16 u16;