fs: remove compat_sys_mount

compat_sys_mount is identical to the regular sys_mount now, so remove it
and use the native version everywhere.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/namespace.c b/fs/namespace.c
index bae0e95..12b431b 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -3072,7 +3072,7 @@ static void shrink_submounts(struct mount *mnt)
 	}
 }
 
-void *copy_mount_options(const void __user * data)
+static void *copy_mount_options(const void __user * data)
 {
 	char *copy;
 	unsigned size;
@@ -3097,7 +3097,7 @@ void *copy_mount_options(const void __user * data)
 	return copy;
 }
 
-char *copy_mount_string(const void __user *data)
+static char *copy_mount_string(const void __user *data)
 {
 	return data ? strndup_user(data, PATH_MAX) : NULL;
 }