MLK-25255-1: ASoC: fsl_rpmsg_i2s: Add clock handler

On i.MX8MP low power audio case, the audiomix module is
shared with M4 core, M4 core need to enable the clock
for SAI and SDMA, but A core don't know this change,
when micfill is used on A core, there is conflict for
audiomix setting. The playback will be blocked on below
case:
      aplay -D"rpmsg" & arecord -D"micfil"

Signed-off-by: Shengjiu Wang <shengjiu.wang@nxp.com>
Reviewed-by: Peng Zhang <peng.zhang_8@nxp.com>
(cherry-picked from commit e5f8f4abf99f1aff26419f1914ea770369fb0ab9)