drm_hwcomposer: Tidy-up DrmDevice class

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

2. Remove DrmDevice self-reference.

3. Replace shared_ptr reference to DrmDevice in DrmFbImporter with a
   pointer, making ResourceManager only owner of DrmDevice and its
   chilren.

Signed-off-by: Roman Stratiienko <roman.o.stratiienko@globallogic.com>
diff --git a/drm/DrmConnector.cpp b/drm/DrmConnector.cpp
index 5e00dd6..4737316 100644
--- a/drm/DrmConnector.cpp
+++ b/drm/DrmConnector.cpp
@@ -63,7 +63,7 @@
 auto DrmConnector::CreateInstance(DrmDevice &dev, uint32_t connector_id,
                                   uint32_t index)
     -> std::unique_ptr<DrmConnector> {
-  auto conn = MakeDrmModeConnectorUnique(dev.fd(), connector_id);
+  auto conn = MakeDrmModeConnectorUnique(dev.GetFd(), connector_id);
   if (!conn) {
     ALOGE("Failed to get connector %d", connector_id);
     return {};
@@ -110,7 +110,7 @@
     return {};
   }
 
-  return MakeDrmModePropertyBlobUnique(drm_->fd(), blob_id);
+  return MakeDrmModePropertyBlobUnique(drm_->GetFd(), blob_id);
 }
 
 bool DrmConnector::IsInternal() const {
@@ -159,7 +159,7 @@
 }
 
 int DrmConnector::UpdateModes() {
-  auto conn = MakeDrmModeConnectorUnique(drm_->fd(), GetId());
+  auto conn = MakeDrmModeConnectorUnique(drm_->GetFd(), GetId());
   if (!conn) {
     ALOGE("Failed to get connector %d", GetId());
     return -ENODEV;