Merge branch 'net-stmmac-Fix-multicast-filter-on-IPQ806x'

Jonathan McDowell says:

====================
net: stmmac: Fix multicast filter on IPQ806x

This pair of patches are the result of discovering a failure to
correctly receive IPv6 multicast packets on such a device (in particular
DHCPv6 requests and RA solicitations). Putting the device into
promiscuous mode, or allmulti, both resulted in such packets correctly
being received. Examination of the vendor driver (nss-gmac from the
qsdk) shows that it does not enable the multicast filter and instead
falls back to allmulti.

Extend the base dwmac1000 driver to fall back when there's no suitable
hardware filter, and update the ipq806x platform to request this.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>