[GFS2] Tidy up bmap/inode code

As per Jan Engelhardt's third set of comments, this make various
code style changes and moves the structures from format.h into
super.c, which was the only place that format.h was actually used.

Cc: Jan Engelhardt <jengelh@linux01.gwdg.de>
Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
diff --git a/fs/gfs2/glops.c b/fs/gfs2/glops.c
index 8e1d8ee..d3e7b08 100644
--- a/fs/gfs2/glops.c
+++ b/fs/gfs2/glops.c
@@ -234,7 +234,6 @@
 		if (flags & DIO_RELEASE)
 			gfs2_ail_empty_gl(gl);
 	}
-
 }
 
 /**
@@ -324,12 +323,11 @@
 	struct gfs2_glock *gl = gh->gh_gl;
 	struct gfs2_inode *ip = gl->gl_object;
 
-	if (ip) {
-		if (test_bit(GLF_DIRTY, &gl->gl_flags))
-			gfs2_inode_attr_in(ip);
-
-		gfs2_meta_cache_flush(ip);
-	}
+	if (ip == NULL)
+		return;
+	if (test_bit(GLF_DIRTY, &gl->gl_flags))
+		gfs2_inode_attr_in(ip);
+	gfs2_meta_cache_flush(ip);
 }
 
 /**