NFS: Use GFP_HIGHUSER for page allocation in nfs_symlink()

nfs_symlink() allocates a GFP_KERNEL page for the pagecache. Most
pagecache pages are allocated using GFP_HIGHUSER, and there's no reason
not to do that in nfs_symlink() as well.
Signed-off-by: Jeff Layton <jlayton@redhat.com>

fs/nfs/dir.c

@@ -1534,7 +1534,7 @@ static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *sym
 
 	lock_kernel();
 
-	page = alloc_page(GFP_KERNEL);
+	page = alloc_page(GFP_HIGHUSER);
 	if (!page) {
 		unlock_kernel();
 		return -ENOMEM;