ASoC: wcd9320: Wait for enough time for Line PAs to get settled

During fast switching of audio playback, we need to wait
for 5ms for the LINE PAs to get settled down before enabling
them again for playback. Same delay is also required after PA
is enabled. Add the required delays after LINE PAs are enabled
or disabled.

CRs-Fixed: 668339
Change-Id: Ie51a88c7a3359660aa416bb23131ca4ac0c49b7a
Signed-off-by: Phani Kumar Uppalapati <phaniu@codeaurora.org>