mailbox: arm_mhu: reduce txpoll_period from 10ms to 1 ms
mailbox: arm_mhu: reduce txpoll_period from 10ms to 1 ms

Since the mailbox core users hrtimers now, it can handle much higher
resolutions. We can reduce the txpoll_period to 1 ms as the transmit
usually takes just few microseconds.

Reported-and-suggested-by: Juri Lelli <8ffba37231b1a282aff9398e255c178f32526c19@arm.com>
Signed-off-by: Sudeep Holla <2f8b50d4d9838571c9f6955972f29e9e41079295@arm.com>
Signed-off-by: Jassi Brar <191fbc354bb0d45dfb103e8f4f6583bfe2bb3ef7@linaro.org>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs