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/stxssa.h b/include/configs/stxssa.h
index 18a673e..08316b6 100644
--- a/include/configs/stxssa.h
+++ b/include/configs/stxssa.h
@@ -427,7 +427,7 @@
 #define CONFIG_NETMASK		255.255.255.0
 #define CONFIG_HOSTNAME		STX_SSA
 #define CONFIG_ROOTPATH		"/gppproot"
-#define CONFIG_BOOTFILE		uImage
+#define CONFIG_BOOTFILE		"uImage"
 #define CONFIG_LOADADDR		0x1000000
 
 #else /* ENV IS IN FLASH		-- use a full-blown envionment */