make init/do_mounts.c:root_device_name static

This patch makes the needlessly global root_device_name static.

Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/init/do_mounts.c b/init/do_mounts.c
index f769fac..3715feb 100644
--- a/init/do_mounts.c
+++ b/init/do_mounts.c
@@ -23,7 +23,7 @@
 int __initdata rd_doload;	/* 1 = load RAM disk, 0 = don't load */
 
 int root_mountflags = MS_RDONLY | MS_SILENT;
-char * __initdata root_device_name;
+static char * __initdata root_device_name;
 static char __initdata saved_root_name[64];
 static int __initdata root_wait;