msm: ipa: add a general function for assert

In order to centralize IPA assert calls and add essential
data on assertion, replace some BUG calls in an ipa_assert wrapper.

CRs-fixed: 1006564
Change-Id: I6a9b679bb083c695908972b377e8779e2f1cca60
Signed-off-by: Amir Levy <alevy@codeaurora.org>