msm: ipa: correct the pointer in idr for FnR stats counter

The stats counter which saved in idr was some stack memory which
could be freed and cause memory corruption. The fix is to use
the memory allocated in heap instead.

Change-Id: Ie398b0271571fcff41cdb85de4d77d202b6552b5
Signed-off-by: Bojun Pan <bojunp@codeaurora.org>