sdm: Fix infinite frame invalidates during camera bandwidth mode change.
During camera bandwidth mode change, need_invalidate is set to true for
 to request new draw cycles to allow new bandwidth mode to take effect.
 This variable is not reset after mode is changed.

Change-Id: Ie9ec20fd1281f97fd5d6b78474cc62cb7d8318ce
CRs-Fixed: 1077284
diff --git a/sdm/libs/hwc/hwc_session.cpp b/sdm/libs/hwc/hwc_session.cpp
index 6aab6d6..a7f4d67 100644
--- a/sdm/libs/hwc/hwc_session.cpp
+++ b/sdm/libs/hwc/hwc_session.cpp
@@ -275,6 +275,7 @@
 
     if (hwc_session->need_invalidate_) {
       hwc_procs->invalidate(hwc_procs);
+      hwc_session->need_invalidate_ = false;
     }
 
     hwc_session->HandleSecureDisplaySession(displays);