drm_hwcomposer: clang-tidy: enable clang-analyzer-* checks

+ fixed existing tidy warnings for these checks.

Signed-off-by: Roman Stratiienko <r.stratiienko@gmail.com>
diff --git a/drm/DrmConnector.cpp b/drm/DrmConnector.cpp
index cfafc1d..7155bf2 100644
--- a/drm/DrmConnector.cpp
+++ b/drm/DrmConnector.cpp
@@ -58,7 +58,7 @@
     ALOGE("Could not get CRTC_ID property\n");
     return ret;
   }
-  ret = UpdateEdidProperty();
+  UpdateEdidProperty();
   if (writeback()) {
     ret = drm_->GetConnectorProperty(*this, "WRITEBACK_PIXEL_FORMATS",
                                      &writeback_pixel_formats_);