drm_hwcomposer: polish for old DRM wrapper code

- deleted private copy constructors
- replace delete with unique_ptr
- use in-class assignment
- remove default constructors/destructors when no longer needed
- remove most iterators used in for loops
- move UniqueFd to its own header so drmresources can use it

Change-Id: Ib20cc0949cf4d381a58548b8156c5cb368ca3efe
diff --git a/drmcrtc.h b/drmcrtc.h
index 9789f12..ad95352 100644
--- a/drmcrtc.h
+++ b/drmcrtc.h
@@ -30,7 +30,8 @@
 class DrmCrtc {
  public:
   DrmCrtc(DrmResources *drm, drmModeCrtcPtr c, unsigned pipe);
-  ~DrmCrtc();
+  DrmCrtc(const DrmCrtc &) = delete;
+  DrmCrtc &operator=(const DrmCrtc &) = delete;
 
   int Init();
 
@@ -46,8 +47,6 @@
   const DrmProperty &mode_property() const;
 
  private:
-  DrmCrtc(const DrmCrtc &);
-
   DrmResources *drm_;
 
   uint32_t id_;