msm: adsprpc: increase max number of concurrent remote sessions

Increase the maximum number of concurrent sessions on one remote
subsystem from 9 to 13, to support the 4 new compute context banks
added in the device-tree.

Change-Id: Id2e8f92a147c3ec37a3622939bb2f23a6605a38a
Acked-by: Thyagarajan Venkatanarayanan <venkatan@qti.qualcomm.com>
Signed-off-by: Himateja Reddy <hmreddy@codeaurora.org>