msm: ipa: Add new IOCTL to enable coalescing

Add a new IOCTL that will enable and set the parameter for
coalescing through IPACM.

Change-Id: I5da2e8147422728510f4c8842a5a8263556d087a
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>
Signed-off-by: Michael Adisumarta <madisuma@codeaurora.org>