QCMAP: Packet counters are not updated in conntrack

Return value of counter api returns s64 instead of u64
Type-casting to the right type.

Change-Id: I8f399ccd52ec4e4f4b23d39f3faa7bb6f23262cc
Acked-by: Vinisha Varre <vvarre@qti.qualcomm.com>
Signed-off-by: Paras Jain <parassin@codeaurora.org>