drm/i915: Add a for_each_intel_connector macro

We have similar macros for crtcs and encoders, and the pattern happens
often enough to justify the macro.

Signed-off-by: Ander Conselvan de Oliveira <ander.conselvan.de.oliveira@intel.com>
Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch>

diff --cc drivers/gpu/drm/i915/i915_debugfs.c
Simple merge

diff --cc drivers/gpu/drm/i915/i915_drv.h
Simple merge

diff --cc drivers/gpu/drm/i915/intel_display.c
Simple merge

diff --cc drivers/gpu/drm/i915/intel_dp_mst.c
Simple merge