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/backend/BackendManager.cpp b/backend/BackendManager.cpp
index aadef36..4a735eb 100644
--- a/backend/BackendManager.cpp
+++ b/backend/BackendManager.cpp
@@ -51,13 +51,13 @@
   display->set_backend(GetBackendByName(backend_name));
   if (display->backend() == nullptr) {
     ALOGE("Failed to set backend '%s' for '%s' and driver '%s'",
-          backend_name.c_str(), display->connector()->name().c_str(),
+          backend_name.c_str(), display->connector()->GetName().c_str(),
           driver_name.c_str());
     return -EINVAL;
   }
 
   ALOGI("Backend '%s' for '%s' and driver '%s' was successfully set",
-        backend_name.c_str(), display->connector()->name().c_str(),
+        backend_name.c_str(), display->connector()->GetName().c_str(),
         driver_name.c_str());
 
   return 0;