ingres: audio: Use default handset mic for raw streams

Stock removed the handset-mic-unprocessed snd_device_name from
raw handset mic usecase, thus falling back to the default handset
mic.

Change-Id: I047c2513af7ebbc31242432a08e4f6ae5867e021
diff --git a/audio/resourcemanager_waipio_mtp.xml b/audio/resourcemanager_waipio_mtp.xml
index 3f0ca55..e53b45d 100644
--- a/audio/resourcemanager_waipio_mtp.xml
+++ b/audio/resourcemanager_waipio_mtp.xml
@@ -160,7 +160,6 @@
             </usecase>
             <usecase>
                 <name>PAL_STREAM_RAW</name>
-                <snd_device_name>handset-mic-unprocessed</snd_device_name>
                 <custom-config key="unprocessed-hdr-mic-landscape">
                     <channels>4</channels>
                     <snd_device_name>unprocessed-hdr-mic-landscape</snd_device_name>