dsp: codecs: Add spin_lock_irqsave instead of spin_lock

spin_lock is acquired in process context and trying do the
operation in process context,while the interrupt came and
the same lock is trying to take in interrupt context which
leads to deadlock.To avoid this we are using spin_lock_irqsave
instead of spin_lock.

Change-Id: I9c4a3ac65d92b0612d7c4845212647c51a72065b
Signed-off-by: Prasad Kumpatla <nkumpat@codeaurora.org>