headers: Update drm.h

This needs the kernel patch to make sure the C++ protection is in place.

Otherwise just new defines, using the right fixed-width types and
some shuffling in where stuff is defined (the DRM_CAP list moved, but
the #defines are the same).

Generated using make headers_install.

Generated fromd drm-misc commit 249c4f538b1aae55d41699f8bafc6cb762a7f48f

Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>