common: cosmetic: CONFIG_ROOTPATH checkpatch compliance

Remove MK_STR from places that consume CONFIG_ROOTPATH 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/mpc5121ads.h b/include/configs/mpc5121ads.h
index 4288894..e284a0f 100644
--- a/include/configs/mpc5121ads.h
+++ b/include/configs/mpc5121ads.h
@@ -526,7 +526,7 @@
 
 #define CONFIG_HOSTNAME		mpc5121ads
 #define CONFIG_BOOTFILE		mpc5121ads/uImage
-#define CONFIG_ROOTPATH		/opt/eldk/ppc_6xx
+#define CONFIG_ROOTPATH		"/opt/eldk/ppc_6xx"
 
 #define CONFIG_LOADADDR		400000	/* default location for tftp and bootm */