[Intel-gfx] [PATCH] drm/irq: Don't call ->get_vblank_counter directly from irq_uninstall/cleanup

[shuang.he at intel.com]

Tested-By: PRC QA PRTS (Patch Regression Test System Contact: shuang.he at intel.com)
Task id: 5805
-------------------------------------Summary-------------------------------------
Platform          Delta          drm-intel-nightly          Series Applied
PNV                 -3              277/277              274/277
ILK                                  313/313              313/313
SNB                                  309/309              309/309
IVB                                  382/382              382/382
BYT                                  296/296              296/296
HSW                                  425/425              425/425
BDW                 -1              318/318              317/318
-------------------------------------Detailed-------------------------------------
Platform  Test                                drm-intel-nightly          Series Applied
*PNV  igt_drm_vma_limiter      PASS(2)      TIMEOUT(1)PASS(1)
*PNV  igt_drm_vma_limiter_cached      NRUN(1)PASS(2)      FAIL(1)PASS(1)
 PNV  igt_gem_userptr_blits_coherency-sync      NO_RESULT(1)CRASH(8)NRUN(1)PASS(8)      CRASH(2)
*BDW  igt_gem_gtt_hog      PASS(23)      DMESG_WARN(1)PASS(1)
Note: You need to pay more attention to line start with '*'