Revert "msm: npu: Trigger IPC interrupt twice to avoid missing interrupt"

This reverts commit 2bd8f670.
It's not needed to trigger IPC interrupt twice to avoid missing
interrupt issue after a write memory barrier is added at the end
of npu_mem_write.

Change-Id: I04d4465f4891af1aeb9e5011522fad720880f0b8
Signed-off-by: Jilai Wang <jilaiw@codeaurora.org>