spmi: qpnp-int: call arbiter ops only when all peripheral irqs are disabled

The current driver calls arbiter ops when an interrupt is being
masked or unmasked. However, the arbiter ops were meant to be
called if all interrupts for a peripheral were disabled or
the first enable happens.  The driver ends up masking the peripheral
(i.e.  all the interrupts in that peripheral) if any one interrupt in
that peripheral is masked. There could be other interrupts enabled
which will not trigger after this.

Fix this by changing the driver to call the arbiter ops only
when all the interrupts in the peripheral are disabled or when
the first enable of an interrupt in that peripheral happens.

Also take this opportunity to clean up the arbiter ops calls to
specifically write to the INT_ACC_ENABLE bit instead of entire
register as specified in the data sheets.

Change-Id: If5835ac125f59d2964242758aa9f9ef145000af7
Signed-off-by: Abhijeet Dharmapurikar <adharmap@codeaurora.org>