asoc: codecs: wcd938x: check for device up before writes

During SSR, codec device will be down and wait till
receiving up notification before doing any register
reads or writes.

Change-Id: I0e2967990bfc9d0d780d4c7e666a4c31159e70ce
Signed-off-by: Karthikeyan Mani <kmani@codeaurora.org>