GROUP_BITFIELDS_BY_ALIGN was long gone, PCC_BITFIELD_TYPE_MATTERS
defaults to 1 in i386.h for all x86 targets.

2018-12-05  Uros Bizjak  <ubizjak@gmail.com>

    * config/i386/cygming.h (PCC_BITFIELD_TYPE_MATTERS): Remove.
    (GROUP_BITFIELDS_BY_ALIGN): Ditto.

Tested by building crosscompiler to x86_64-w64-mingw32.

Committed to mainline SVN as obvious.

Uros.