ASoC: wcd_cpe_core: Improve exception error handling

CPE (Codec Processing Engine) block in the hardware has multiple
exception interrupts. When CPE crashes, it is possible it will generate
multiple and spurious exception interrupts. This is causing some
interrupts to be missed. Fix this by making sure interrupts that are
serviced are masked to avoid spurious interrupts and pending interrupts
are serviced to avoid missing interrupts.

CRs-fixed: 874196
Change-Id: I63f3ef2eac3f194d5e535c607893236d3ae6a4ab
Signed-off-by: Bhalchandra Gajare <gajare@codeaurora.org>