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/MPC8540ADS.h b/include/configs/MPC8540ADS.h
index 85211cf..ae94a4a 100644
--- a/include/configs/MPC8540ADS.h
+++ b/include/configs/MPC8540ADS.h
@@ -438,7 +438,7 @@
 
 #define CONFIG_HOSTNAME		unknown
 #define CONFIG_ROOTPATH		"/nfsroot"
-#define CONFIG_BOOTFILE		your.uImage
+#define CONFIG_BOOTFILE		"your.uImage"
 
 #define CONFIG_SERVERIP  192.168.1.1
 #define CONFIG_GATEWAYIP 192.168.1.1