xfs: remove xfs_attr_leaf_hasname

In the Linux kernel, the following vulnerability has been resolved: xfs: remove xfs_attr_leaf_hasname The calling convention of xfs_attr_leaf_hasname() is problematic, because it returns a NULL buffer when xfs_attr3_leaf_read fails, a valid buffer when xfs_attr3_leaf_lookup_int returns -ENOATTR or -EEXIST, and a non-NULL buffer pointer for an already released buffer when xfs_attr3_leaf_lookup_int fails with other error values. Fix this by simply open coding xfs_attr_leaf_hasname in the callers, so that the buffer release code is done by each caller of xfs_attr3_leaf_read.