Prima: Fix RX of broadcast packets (JIRA NIGHTLIES-98)

This matches a revert to be done in kitkat-mr3-rel-ghost branch
of MotorolaMobilityLLC/vendor-qcom-opensource-wlan-prima repo:

Revert "Implement new IPV6 filter logic"

This reverts commit 5d5df49372fdb5cda00c18c9367ff31bed16f976.

Conflicts:

        CORE/HDD/src/wlan_hdd_assoc.c
        CORE/HDD/src/wlan_hdd_main.c
        CORE/MAC/inc/qwlan_version.h

Change-Id: Ic456128084149abebd82e698052d644458c24de6