be2net: don't enable multicast flag in be_enable_if_filters() routine

When the interface is opened (in be_open()) the routine
be_enable_if_filters() must be called to switch on the basic filtering
capabilities of an interface that are not changed at run-time.
These include the flags UNTAGGED, BROADCAST and PASS_L3L4_ERRORS.
Other flags such as MULTICAST and PROMISC must be enabled later by
be_set_rx_mode() based on the state in the netdev/adapter struct.

be_enable_if_filters() routine is wrongly trying to enable MULTICAST flag
without checking the current adapter state. This can cause the RX_FILTER
cmds to the FW to fail.  This patch fixes this problem by only enabling
the basic filtering flags in be_enable_if_filters().

The VF must be able to issue RX_FILTER cmd with any filter flag, as long
as the PF allowed those flags (if_cap_flags) in the iface it provisioned
for the VF. This rule is applicable even when the VF doesn't have the
FILTMGMT privilege. There is a bug in BE3 FW that wrongly fails RX_FILTER
multicast programming cmds on VFs that don't have FILTMGMT privilege.
This patch also helps in insulating the VF driver from be_open failures due
to the FW bug. A fix for the BE3 FW issue will be available in
versions >= 11.0.283.0 and 10.6.334.0

Reported-by: Ivan Vecera <ivecera@redhat.com>
Signed-off-by: Venkat Duvvuru <venkatkumar.duvvuru@avagotech.com>
Signed-off-by: Sathya Perla <sathya.perla@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>