huashan: fixup buggy mic (add a missing flag)

looks like we missed a flag
When a person switches the call into loudspeaker mode,
suddenly alsa starts using rear mic as "main" mic,
 and it pretty much renders it unusable if you hold the phone the usual way.

this fixes it :) - needs a little more testing

Props to @peters. and @MrSteve555 for informing me about this.

Change-Id: I5ee16c0c31156e3b4d1e65621bb032d35ee1ad6f