binutils: drop *.texi* hunks from xtensa trampolines patches

Rebuilding as.info with makeinfo version 5.2 results in a build error,
even with pristine binutils source. Dropping hunks that change *.texi*
files avoids documentation rebuild.

Reported-by: Vincent Stehlé <vincent.stehle@freescale.com>
Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>