[Intel-gfx] [PATCH v3] drm/i915: Disable the mmio.debug WARN after it fires

[shuang.he at intel.com]

Tested-By: PRC QA PRTS (Patch Regression Test System Contact: shuang.he at intel.com)
-------------------------------------Summary-------------------------------------
Platform          Delta          drm-intel-nightly          Series Applied
PNV                 -3              364/364              361/364
ILK              +1-4              364/366              361/366
SNB                 -1              448/450              447/450
IVB                 -2              497/498              495/498
BYT                 -1              289/289              288/289
HSW                 -1              563/564              562/564
BDW                 -1              416/417              415/417
-------------------------------------Detailed-------------------------------------
Platform  Test                                drm-intel-nightly          Series Applied
 PNV  igt_gem_exec_blt      NRUN(2, M23M7)PASS(1, M25)      NRUN(1, M7)
*PNV  igt_gen3_mixed_blits      PASS(2, M25M7)      FAIL(1, M7)
*PNV  igt_gen3_render_tiledx_blits      PASS(2, M25M7)      FAIL(1, M7)
 ILK  igt_gem_exec_blt      NRUN(2, M37M26)PASS(1, M26)      NRUN(1, M26)
*ILK  igt_kms_flip_rcs-wf_vblank-vs-dpms-interruptible      PASS(2, M26)      DMESG_WARN(1, M26)
 ILK  igt_kms_render_direct-render      DMESG_WARN(1, M26)PASS(1, M26)      DMESG_WARN(1, M26)
 ILK  igt_kms_flip_bcs-flip-vs-modeset-interruptible      DMESG_WARN(1, M26)PASS(6, M37M26)      PASS(1, M26)
*ILK  igt_kms_flip_rcs-flip-vs-modeset      PASS(2, M26)      DMESG_WARN(1, M26)
 SNB  igt_gem_exec_blt      NRUN(3, M35M22)PASS(1, M35)      NRUN(1, M22)
 IVB  igt_gem_exec_blt      NRUN(3, M34M21M4)PASS(1, M34)      NRUN(1, M21)
*IVB  igt_kms_cursor_crc_cursor-128x128-random      PASS(2, M34M21)      DMESG_WARN(1, M21)
 BYT  igt_gem_exec_blt      NRUN(3, M48M49M50)PASS(1, M48)      NRUN(1, M49)
 HSW  igt_gem_exec_blt      NRUN(3, M40M20M19)PASS(1, M40)      NRUN(1, M20)
 BDW  igt_gem_exec_blt      NRUN(2, M30M28)PASS(1, M28)      NRUN(1, M28)
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