MFC r275816:

MFC r275816:
  Fix a bug introdiced in r217548.  According to NS DP83815 data
  sheet, RX filter should be disabled before programming.
  Previously it was clearing wrong bits so RX filter was not
  disabled in RX filter configuration.

MFC r277048:
  Enable receive filter in sis_rxfilter().
  While I'm here add a check for driver running state for multicast
  filter handling.

git-svn-id: svn://svn.freebsd.org/base/stable/9@280658 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f