msm: sps: improve BAM inactivity timer function

1> Add the support for BAM global inactivity timer which is a new feature
in B family.
2> There is an update that changes the time unit of the inactivity timer
counter from 0.1ms to 0.125ms. Thus, we adjust the parameter in SW driver
for this update.
3> Inactivity timer timeout interrupt will become a new type of BAM global
interrupts, and it is a normal interrupt different from other BAM global
error interrupts. Thus, change the log level for callback message from INFO
to DEBUG.
4> Change timer result argument of inactivity timer API to an optional one
for client drivers.

Change-Id: If223ef311f0393f2f2243f6b8a862fe760ff5214
Signed-off-by: Yan He <yanhe@codeaurora.org>