ceph: kill ceph_osdc_writepages() "dosync" parameter

There is only one caller of ceph_osdc_writepages(), and it always
passes 0 as its "dosync" argument.  Get rid of that argument and
replace its use in ceph_osdc_writepages() with 0.

Signed-off-by: Alex Elder <elder@inktank.com>
Reviewed-by: Josh Durgin <josh.durgin@inktank.com>
diff --git a/net/ceph/osd_client.c b/net/ceph/osd_client.c
index dd01b13..ac186b7 100644
--- a/net/ceph/osd_client.c
+++ b/net/ceph/osd_client.c
@@ -1867,7 +1867,7 @@
 			 u32 truncate_seq, u64 truncate_size,
 			 struct timespec *mtime,
 			 struct page **pages, int num_pages,
-			 int flags, int do_sync)
+			 int flags)
 {
 	struct ceph_osd_request *req;
 	int rc = 0;
@@ -1878,7 +1878,7 @@
 				    CEPH_OSD_OP_WRITE,
 				    flags | CEPH_OSD_FLAG_ONDISK |
 					    CEPH_OSD_FLAG_WRITE,
-				    snapc, do_sync,
+				    snapc, 0,
 				    truncate_seq, truncate_size, mtime,
 				    true, 1, page_align);
 	if (IS_ERR(req))