hal: change voice call sequence on APQ targets

Send device disable command to external modem before voice call
mixer controls are disabled on APQ side. Enable device command
also should be sent only after enabling mixer controls on APQ side.

Change-Id: I2e4dc321b16f695564460771b3656cd2c4a089a9
diff --git a/hal/platform_api.h b/hal/platform_api.h
index dac3fd9..44ad790 100644
--- a/hal/platform_api.h
+++ b/hal/platform_api.h
@@ -32,6 +32,9 @@
 int platform_switch_voice_call_device_post(void *platform,
                                            snd_device_t out_snd_device,
                                            snd_device_t in_snd_device);
+int platform_switch_voice_call_usecase_route_post(void *platform,
+                                                  snd_device_t out_snd_device,
+                                                  snd_device_t in_snd_device);
 int platform_start_voice_call(void *platform, uint32_t vsid);
 int platform_stop_voice_call(void *platform, uint32_t vsid);
 int platform_set_voice_volume(void *platform, int volume);