The hardware can only be set to strip or not strip both the VLAN CTAG and
STAG.  It cannot strip one and not strip the other.  Add logic to
bnxt_fix_features() to toggle both feature flags when the user is toggling
one of them.

Signed-off-by: Michael Chan <michael.chan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>