Merge tag 'libdrm-2.4.12' into debian-unstable

Conflicts:
	linux-core/Makefile
	linux-core/Makefile.kernel
	linux-core/drmP.h
	linux-core/drm_agpsupport.c
	linux-core/drm_compat.c
	linux-core/drm_drv.c
	linux-core/drm_fops.c
	linux-core/drm_os_linux.h
	linux-core/drm_proc.c
	linux-core/drm_stub.c
	linux-core/drm_sysfs.c
	linux-core/drm_vm.c
	linux-core/nouveau_backlight.c
	linux-core/xgi_cmdlist.c
	linux-core/xgi_drv.c
	linux-core/xgi_drv.h
	linux-core/xgi_fence.c
	shared-core/nouveau_drv.h
	shared-core/nouveau_reg.h
	shared-core/nv50_graph.c
	shared-core/via_drv.c
	shared-core/via_drv.h
	shared-core/via_map.c