libx11: remove unused patch and FILESEXTRAPATHS

* 0001-fix-a-memory-leak-in-XRegisterIMInstantiateCallback.patch was removed
  from SRC_URI in:
  https://git.openembedded.org/openembedded-core/commit/?id=e13f651f73db0f26f4645447ab5fa17e36d1903b



Signed-off-by: Martin Jansa <Martin.Jansa@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
(cherry picked from commit ee37d9f0)
Signed-off-by: Steve Sakoman <steve@sakoman.com>