msm: ipa3: Add support for IPA/GSI register dump/collection

Add functionality to the IPA/GSI driver in support of a register
dump/collection feature.  Register's values are collected upon system
crash.

Change-Id: I6ccc5a801fd2cf9cd8e92ad4e2c9244a88fae393
CRs-Fixed: 2342813
Acked-by: Perry Randise <prandise@qti.qualcomm.com>
Signed-off-by: Jennifer L. Zenner <jzenner@codeaurora.org>