proc_devtree: Replace include linux/module.h with linux/export.h

Since it uses only THIS_MODULE macro, include <linux/export.h>
is the right to go here.
Signed-off-by: Syam Sidhardhan <s.syam@samsung.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

fs/proc/proc_devtree.c

@@ -12,7 +12,7 @@
 #include <linux/stat.h>
 #include <linux/string.h>
 #include <linux/of.h>
-#include <linux/module.h>
+#include <linux/export.h>
 #include <linux/slab.h>
 #include <asm/prom.h>
 #include <asm/uaccess.h>