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/gr_cpci_ax2000.h b/include/configs/gr_cpci_ax2000.h
index a127a2b..0ec4af6 100644
--- a/include/configs/gr_cpci_ax2000.h
+++ b/include/configs/gr_cpci_ax2000.h
@@ -135,7 +135,7 @@
 #define CONFIG_GATEWAYIP 192.168.0.1
 #define CONFIG_SERVERIP 192.168.0.20
 #define CONFIG_IPADDR 192.168.0.206
-#define CONFIG_ROOTPATH /export/rootfs
+#define CONFIG_ROOTPATH "/export/rootfs"
 #define CONFIG_HOSTNAME  ax2000
 #define CONFIG_BOOTFILE  /uImage