drm: Extract drm_connector.[hc]

Pulls in quite a lot of connector related structures (cmdline mode,
force/status enums, display info), but I think that all makes perfect
sense.

Also had to move a few more core kms object stuff into drm_modeset.h.

And as a first cleanup remove the kerneldoc for the 2 connector IOCTL
- DRM core docs are aimed at drivers, no point documenting internal in
excruciating detail.

v2: And also pull in all the connector property code.

Reviewed-by: Sean Paul <seanpaul@chromium.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Link: http://patchwork.freedesktop.org/patch/msgid/1471034937-651-14-git-send-email-daniel.vetter@ffwll.ch

Documentation/gpu/drm-kms.rst

@@ -110,6 +110,15 @@ Display Modes Function Reference
 .. kernel-doc:: drivers/gpu/drm/drm_modes.c
    :export:
 
+Connector Display Sink Abstraction
+==================================
+
+.. kernel-doc:: include/drm/drm_connector.h
+   :internal:
+
+.. kernel-doc:: drivers/gpu/drm/drm_connector.c
+   :export:
+
 KMS Initialization and Cleanup
 ==============================
 

drivers/gpu/drm/Makefile

@@ -13,7 +13,7 @@ drm-y       :=	drm_auth.o drm_bufs.o drm_cache.o \
 		drm_trace_points.o drm_global.o drm_prime.o \
 		drm_rect.o drm_vma_manager.o drm_flip_work.o \
 		drm_modeset_lock.o drm_atomic.o drm_bridge.o \
-		drm_framebuffer.o
+		drm_framebuffer.o drm_connector.o
 
 drm-$(CONFIG_COMPAT) += drm_ioc32.o
 drm-$(CONFIG_DRM_GEM_CMA_HELPER) += drm_gem_cma_helper.o