drm_hwcomposer: Tidy-up DrmConnector class

Implement DrmConnector instantiation through CreateInstance() static method,
which helps to reduce complexity of DrmDevice::Init() function.

Move Connector-to-CRTC binding information to the DrmDevice class.

Move drm/DrmConnector.h to Normal clang-tidy checks list by fixing
clang-tidy findings.

Signed-off-by: Roman Stratiienko <roman.o.stratiienko@globallogic.com>
diff --git a/hwc2_device/HwcDisplayConfigs.cpp b/hwc2_device/HwcDisplayConfigs.cpp
index 16f1ed0..f6ccdb7 100644
--- a/hwc2_device/HwcDisplayConfigs.cpp
+++ b/hwc2_device/HwcDisplayConfigs.cpp
@@ -61,14 +61,14 @@
     return HWC2::Error::BadDisplay;
   }
 
-  if (connector.modes().empty()) {
+  if (connector.GetModes().empty()) {
     ALOGE("No modes reported by KMS");
     return HWC2::Error::BadDisplay;
   }
 
   hwc_configs.clear();
-  mm_width = connector.mm_width();
-  mm_height = connector.mm_height();
+  mm_width = connector.GetMmWidth();
+  mm_height = connector.GetMmHeight();
 
   preferred_config_id = 0;
   int preferred_config_group_id = 0;
@@ -77,7 +77,7 @@
   int last_group_id = 1;
 
   /* Group modes */
-  for (const auto &mode : connector.modes()) {
+  for (const auto &mode : connector.GetModes()) {
     /* Find group for the new mode or create new group */
     int group_found = 0;
     for (auto &hwc_config : hwc_configs) {