msm: bam_dmux: Improve robustness of A2 State Changes

Add code to handle unexpected A2 disconnects while
in polling mode and defer polling-to-interrupt
mode switch upon reconnect.

CRs-Fixed: 323592
Change-Id: I13ee41c29c429d70e060c64c46e7bcf590f23565
Signed-off-by: Eric Holmberg <eholmber@codeaurora.org>
1 file changed