msm: ipa: Add support for IPA unit-test framework

Add IPA unit-test framework. The framework supports
definition and execution of tests that are grouped
into suites according to IPA functional blocks.
Debugfs file system is being used as a user interface.
An example test suite is added for reference.

Change-Id: Ide4ed54970c62f6485809c3bd63960536b4ace4f
CRs-Fixed: 1040200
Signed-off-by: Ghanim Fodi <gfodi@codeaurora.org>