radio: iris: Allow task to be interrupted

Not allowing task to be interrupted can cause
delay in response to upper layer. Allow task pending
to be interrupted when corresponding command's status
is received.

Change-Id: Ibb84673dfa92458c1ef45da12e63dd041abd0c39
CRs-Fixed: 569318
Signed-off-by: Ayaz Ahmad <aahmad@codeaurora.org>