common: cosmetic: CONFIG_BOOTFILE checkpatch compliance

Remove MK_STR from places that consume CONFIG_BOOTFILE to force all definitions to be string literals.

Signed-off-by: Joe Hershberger <joe.hershberger@ni.com>
Cc: Joe Hershberger <joe.hershberger@gmail.com>
Cc: Wolfgang Denk <wd@denx.de>
Acked-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/include/configs/gr_xc3s_1500.h b/include/configs/gr_xc3s_1500.h
index 8973955..7e8e6f5 100644
--- a/include/configs/gr_xc3s_1500.h
+++ b/include/configs/gr_xc3s_1500.h
@@ -101,7 +101,7 @@
 #define CONFIG_IPADDR 192.168.0.206
 #define CONFIG_ROOTPATH "/export/rootfs"
 #define CONFIG_HOSTNAME  grxc3s1500
-#define CONFIG_BOOTFILE  /uImage
+#define CONFIG_BOOTFILE "/uImage"
 
 #define CONFIG_BOOTCOMMAND	"run flash_self"