msm: ipa: fix the GRO agg_count error

For mergeing ipav3 codes with ipav2, the
GRO feature is broken due to the wrong agg_count
parameter passed to IPA which always exceeds the
limit ipa-HW can take. The fix is to pass right
paratemer instead.

Change-Id: I0f2e0d503715d684e43ca41db44d56523079ae3c
Signed-off-by: Skylar Chang <chiaweic@codeaurora.org>