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/DrmEncoder.cpp b/drm/DrmEncoder.cpp
index 8049a5c..eed5b5f 100644
--- a/drm/DrmEncoder.cpp
+++ b/drm/DrmEncoder.cpp
@@ -29,7 +29,7 @@
 
 auto DrmEncoder::CreateInstance(DrmDevice &dev, uint32_t encoder_id,
                                 uint32_t index) -> std::unique_ptr<DrmEncoder> {
-  auto e = MakeDrmModeEncoderUnique(dev.fd(), encoder_id);
+  auto e = MakeDrmModeEncoderUnique(dev.GetFd(), encoder_id);
   if (!e) {
     ALOGE("Failed to get encoder %d", encoder_id);
     return {};