bnxt_en: Use correct src_fid to determine direction of the flow

Direction of the flow is determined using src_fid. For an RX flow,
src_fid is PF's fid and for TX flow, src_fid is VF's fid. Direction
of the flow must be specified, when getting statistics for that flow.
Currently, for DECAP flow, direction is determined incorrectly, i.e.,
direction is initialized as TX for DECAP flow, instead of RX. Because
of which, stats are not reported for this DECAP flow, though it is
offloaded and there is traffic for that flow, resulting in flow age out.

This patch fixes the problem by determining the DECAP flow's direction
using correct fid.  Set the flow direction in all cases for consistency
even if 64-bit flow handle is not used.

Fixes: abd43a13 ("bnxt_en: Support for 64-bit flow handle.")
Signed-off-by: Venkat Duvvuru <venkatkumar.duvvuru@broadcom.com>
Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>