net/bnxt: fix enable/disable VLAN filtering

net/bnxt: fix enable/disable VLAN filtering

There is no condition check for the user requested operation
for VLAN filtering. As a result, VLAN filtering is getting disabled
when the user enables/disables VLAN stripping on same port.

The function bnxt_hwrm_clear_l2_filter() didn't actually free
L2 filter in HW if the reference count of filter is zero.

Fixed it by incrementing the reference count of filter in
bnxt_alloc_filter() routine.

Because of the recent changes in bnxt_hwrm_clear_l2_filter(),
change was needed in the routine bnxt_set_default_mac_addr_op()
to destroy and re-create the default filter when the user
changes the default MAC of the port.

Fixes: 5c1171c97216 ("net/bnxt: refactor filter/flow")
Fixes: 6118503d8071 ("net/bnxt: fix VLAN filtering")
Cc: stable@dpdk.org
Signed-off-by: Kalesh AP <kalesh-anakkur.purayil@broadcom.com>
Reviewed-by: Somnath Kotur <somnath.kotur@broadcom.com>
Reviewed-by: Ajit Khaparde <ajit.khaparde@broadcom.com>