reiserfs: switch to generic_{get,set,remove}xattr()

reiserfs_xattr_[sg]et() will fail with -EOPNOTSUPP for V1 inodes anyway,
and all reiserfs instances of ->[sg]et() call it and so does ->set_acl().

Checks for name length in the instances had been bogus; they should've
been "bugger off if it's _exactly_ the prefix" (as generic would
do on its own) and not "bugger off if it's shorter than the prefix" -
that can't happen.

xattr_full_name() is needed to adjust for the fact that generic instances
will skip the prefix in the name passed to ->[gs]et(); reiserfs homegrown
analogues didn't.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/reiserfs/namei.c b/fs/reiserfs/namei.c
index 2a12d46..8a36696 100644
--- a/fs/reiserfs/namei.c
+++ b/fs/reiserfs/namei.c
@@ -1650,10 +1650,10 @@
 	.mknod = reiserfs_mknod,
 	.rename = reiserfs_rename,
 	.setattr = reiserfs_setattr,
-	.setxattr = reiserfs_setxattr,
-	.getxattr = reiserfs_getxattr,
+	.setxattr = generic_setxattr,
+	.getxattr = generic_getxattr,
 	.listxattr = reiserfs_listxattr,
-	.removexattr = reiserfs_removexattr,
+	.removexattr = generic_removexattr,
 	.permission = reiserfs_permission,
 	.get_acl = reiserfs_get_acl,
 	.set_acl = reiserfs_set_acl,
@@ -1667,10 +1667,10 @@
 	.readlink = generic_readlink,
 	.get_link	= page_get_link,
 	.setattr = reiserfs_setattr,
-	.setxattr = reiserfs_setxattr,
-	.getxattr = reiserfs_getxattr,
+	.setxattr = generic_setxattr,
+	.getxattr = generic_getxattr,
 	.listxattr = reiserfs_listxattr,
-	.removexattr = reiserfs_removexattr,
+	.removexattr = generic_removexattr,
 	.permission = reiserfs_permission,
 };
 
@@ -1679,10 +1679,10 @@
  */
 const struct inode_operations reiserfs_special_inode_operations = {
 	.setattr = reiserfs_setattr,
-	.setxattr = reiserfs_setxattr,
-	.getxattr = reiserfs_getxattr,
+	.setxattr = generic_setxattr,
+	.getxattr = generic_getxattr,
 	.listxattr = reiserfs_listxattr,
-	.removexattr = reiserfs_removexattr,
+	.removexattr = generic_removexattr,
 	.permission = reiserfs_permission,
 	.get_acl = reiserfs_get_acl,
 	.set_acl = reiserfs_set_acl,