GFS2: Reduce struct gfs2_trans in size

A couple of "int" fields were being used as boolean values
so we can make them bitfields of one bit, and put them in
what might otherwise be a hole in the structure with 64
bit alignment.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>

diff --cc fs/gfs2/incore.h
Simple merge

diff --cc fs/gfs2/trans.c
Simple merge