mhi: Allow ipc logging in perf build

MHI ipc verbose level logs gets compiled out in perf build.
Enable ipc logging when log level is set to MHI_MSG_LVL_VERBOSE.
This allows to enable mhi ipc logging on demand when log level
is changed to MHI_MSG_LVL_VERBOSE form MHI_MSG_LVL_ERROR in perf
build.

Change-Id: I63c6cd6922f12c8d31061de9cbb27e2101e5758b
Signed-off-by: Hemant Kumar <hemantk@codeaurora.org>