heal/src: Fix build failure on OSX

Fix involves removing GF_GLUSTERFS_CFLAGS is a
non-existent configure value, use GF_CFLAGS instead

Change-Id: Id5e29f46589dd75c1f71c53ffaf8af60584782c7
BUG: 1089172
Signed-off-by: Harshavardhana <harsha@harshavardhana.net>
Reviewed-on: http://review.gluster.org/8942
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Justin Clift <justin@gluster.org>
Tested-by: Justin Clift <justin@gluster.org>