[Intel-gfx] [PATCH 5/5] drm/i915: Enable PSR by default.

[shuang.he at intel.com]

Tested-By: Intel Graphics QA PRTS (Patch Regression Test System Contact: shuang.he at intel.com)
Task id: 6180
-------------------------------------Summary-------------------------------------
Platform          Delta          drm-intel-nightly          Series Applied
PNV                 -5              276/276              271/276
ILK                                  301/301              301/301
SNB                                  316/316              316/316
IVB                                  328/328              328/328
BYT                                  285/285              285/285
HSW                                  394/394              394/394
BDW                                  321/321              321/321
-------------------------------------Detailed-------------------------------------
Platform  Test                                drm-intel-nightly          Series Applied
*PNV  igt at gem_fence_thrash@bo-write-verify-none      PASS(2)      FAIL(1)PASS(1)
*PNV  igt at gem_fence_thrash@bo-write-verify-threaded-none      PASS(2)      FAIL(1)PASS(1)
*PNV  igt at gem_fence_thrash@bo-write-verify-x      PASS(2)      FAIL(1)PASS(1)
*PNV  igt at gem_fence_thrash@bo-write-verify-y      PASS(2)      FAIL(1)PASS(1)
 PNV  igt at gen3_render_mixed_blits      FAIL(4)PASS(4)      FAIL(1)PASS(1)
Note: You need to pay more attention to line start with '*'