[9p] Introduce client side TFSYNC/RFSYNC for dotl.

SYNOPSIS
    size[4] Tfsync tag[2] fid[4]

    size[4] Rfsync tag[2]

DESCRIPTION

The Tfsync transaction transfers ("flushes") all modified in-core data of
file identified by fid to the disk device (or other  permanent  storage
device)  where that  file  resides.

Signed-off-by: Venkateswararao Jujjuri <jvrao@linux.vnet.ibm.com>
Signed-off-by: Eric Van Hensbergen <ericvh@gmail.com>
diff --git a/include/net/9p/9p.h b/include/net/9p/9p.h
index a4a1b04..55e9605 100644
--- a/include/net/9p/9p.h
+++ b/include/net/9p/9p.h
@@ -163,6 +163,8 @@
 	P9_RXATTRCREATE,
 	P9_TREADDIR = 40,
 	P9_RREADDIR,
+	P9_TFSYNC = 50,
+	P9_RFSYNC,
 	P9_TLINK = 70,
 	P9_RLINK,
 	P9_TMKDIR = 72,