[Intel-gfx] [PATCH] drm/i915: add i915 specific connector debugfs file for DPCD

[shuang.he at intel.com]

Tested-By: PRC QA PRTS (Patch Regression Test System Contact: shuang.he at intel.com)
Task id: 5824
-------------------------------------Summary-------------------------------------
Platform          Delta          drm-intel-nightly          Series Applied
PNV                                  282/282              282/282
ILK                 -1              308/308              307/308
SNB                                  326/326              326/326
IVB                                  379/379              379/379
BYT                                  294/294              294/294
HSW                 -2              387/387              385/387
BDW                 -1              316/316              315/316
-------------------------------------Detailed-------------------------------------
Platform  Test                                drm-intel-nightly          Series Applied
*ILK  igt_drv_suspend_debugfs-reader      PASS(1)      DMESG_WARN(2)
*HSW  igt_gem_storedw_loop_blt      PASS(1)      DMESG_WARN(1)PASS(1)
*HSW  igt_pm_rpm_debugfs-read      PASS(1)      DMESG_WARN(2)
*BDW  igt_gem_gtt_hog      PASS(1)      DMESG_WARN(1)PASS(1)
Note: You need to pay more attention to line start with '*'