New helper - current_umask()

current->fs->umask is what most of fs_struct users are doing.
Put that into a helper function.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/jffs2/acl.c b/fs/jffs2/acl.c
index d987137..77ccf8c 100644
--- a/fs/jffs2/acl.c
+++ b/fs/jffs2/acl.c
@@ -336,7 +336,7 @@
 		return PTR_ERR(acl);
 
 	if (!acl) {
-		*i_mode &= ~current->fs->umask;
+		*i_mode &= ~current_umask();
 	} else {
 		if (S_ISDIR(*i_mode))
 			jffs2_iset_acl(inode, &f->i_acl_default, acl);