xdriver_xf86-video-intel: add upstream patch fixing libdrm/kernel crash

When running this Intel driver with a newer libdrm/kernel (4.x), Xorg
can crash (segmentation fault).

References:
 http://cgit.freedesktop.org/xorg/driver/xf86-video-intel/commit/?id=7fe2b2948652443ff43d907855bd7a051d54d309
 https://bugs.gentoo.org/show_bug.cgi?id=552124
 https://bugzilla.opensuse.org/show_bug.cgi?id=931917



[Thomas:
  - add upstream link to the git commits in the patches themselves
  - add James SoB line inside the patches themselves]

Signed-off-by: James Knight <james.knight@rockwellcollins.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>