cifs: Remove explicit handling of IO_REPARSE_TAG_MOUNT_POINT in inode.c

IO_REPARSE_TAG_MOUNT_POINT is just a specific case of directory Name
Surrogate reparse point. As reparse_info_to_fattr() already handles all
directory Name Surrogate reparse point (done by the previous change),
there is no need to have explicit case for IO_REPARSE_TAG_MOUNT_POINT.

Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Steve French <stfrench@microsoft.com>