dsp: q6voice: Adds checks for an integer overflow

there is no check for cvs_voc_pkt[2],when recieves
0xffffffff from ADSP which results in an integer overflow
Fix is to address this.

Change-Id: Ie935dd8823981ec260d77f5117f4ef0b0fc08f60
Signed-off-by: Ramireddy KrishnaKanth Reddy <quic_ramikris@quicinc.com>
(cherry picked from commit 4524418cd14dce47e4ea7234618f919e28dbbe5a)
Signed-off-by: Sandhya Mutha Naga Venkata <quic_smuthana@quicinc.com>