hal: retry failed MBDRC cal level

- in the start of the playback since usecase list is empty
  or not populated with the current usecase (which will be added
  on the first write) unless volume is changed when playing music
  correct gain level is not selected
- cache gain level on failure and trigger set gain level when a
  new usecase is added

Bug 30503798 29933450

Change-Id: I3d199a2810d34a693a099e3cf4b635d5b156a317
diff --git a/hal/msm8916/platform.c b/hal/msm8916/platform.c
index 683723f..52e9fd8 100644
--- a/hal/msm8916/platform.c
+++ b/hal/msm8916/platform.c
@@ -599,7 +599,7 @@
 
 bool platform_send_gain_dep_cal(void *platform __unused, int level __unused)
 {
-    return 0;
+    return true;
 }
 
 void platform_set_echo_reference(struct audio_device *adev, bool enable,