ASoC:wcd9304:RX voice call is distorted in handset device

Issue:The RX voice call is distorted from handset,after reboot
          the device its working as expected.
Root cause:This happens due enable override gain in cp_static
            register
Fix:Configure the cp_static override gain as Half gain

Change-Id: I67e6c41ef4fb5f7059a251bcc5bc1e4686b7cc29
CRs-Fixed: 532155
Signed-off-by: Mohammad Johny Shaik <mjshai@codeaurora.org>