msm: ipa: mark the IPA clock on in virtual/emulation mode

The IPA enable/disable clock logic will be stubbed out on virtual
or emulation mode. The change here is to set the IPA clock flag
to true always and assume we always have IPA clock on.

Change-Id: Ibece0630033a8cd129461e6831ecfc85f00e2121
Signed-off-by: Bojun Pan <bojunp@codeaurora.org>