xfs: convert attr to use unsigned names

To be consistent with the directory code, the attr code should use
unsigned names. Convert the names from the vfs at the highest level
to unsigned, and ænsure they are consistenly used as unsigned down
to disk.

Signed-off-by: Dave Chinner <david@fromorbit.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
diff --git a/fs/xfs/xfs_vnodeops.h b/fs/xfs/xfs_vnodeops.h
index 167a467..774f407 100644
--- a/fs/xfs/xfs_vnodeops.h
+++ b/fs/xfs/xfs_vnodeops.h
@@ -43,11 +43,11 @@
 int xfs_rename(struct xfs_inode *src_dp, struct xfs_name *src_name,
 		struct xfs_inode *src_ip, struct xfs_inode *target_dp,
 		struct xfs_name *target_name, struct xfs_inode *target_ip);
-int xfs_attr_get(struct xfs_inode *ip, const char *name, char *value,
-		int *valuelenp, int flags);
-int xfs_attr_set(struct xfs_inode *dp, const char *name, char *value,
-		int valuelen, int flags);
-int xfs_attr_remove(struct xfs_inode *dp, const char *name, int flags);
+int xfs_attr_get(struct xfs_inode *ip, const unsigned char *name,
+		unsigned char *value, int *valuelenp, int flags);
+int xfs_attr_set(struct xfs_inode *dp, const unsigned char *name,
+		unsigned char *value, int valuelen, int flags);
+int xfs_attr_remove(struct xfs_inode *dp, const unsigned char *name, int flags);
 int xfs_attr_list(struct xfs_inode *dp, char *buffer, int bufsize,
 		int flags, struct attrlist_cursor_kern *cursor);
 ssize_t xfs_read(struct xfs_inode *ip, struct kiocb *iocb,