dsp: codecs: use native API to configure PCM output block in multiaac

Usage of q6asm_enc_cfg_blk_pcm() does not trigger
PortSettingsChanged event which is required for multi aac component.
Configure the PCM output block using q6asm_enc_cfg_blk_pcm_native()
which ensures that the event gets triggered.

Change-Id: Ieefeead45435840c2ecc1c072e8095785fd4b583
Signed-off-by: Satya Krishna Pindiproli <satyak@codeaurora.org>
Signed-off-by: Soumya Managoli <smanag@codeaurora.org>