mptcp: fix typos in comments

This patch fixes the spelling mistakes in comments.
greter -> greater

Signed-off-by: moyuanhao <moyuanhao3676@163.com>

Author: moss-mo-yy

net/mptcp/protocol.c

@@ -1376,7 +1376,7 @@ struct sock *mptcp_subflow_get_send(struct mptcp_sock *msk)
 	 * - estimate the faster flow linger time
 	 * - use the above to estimate the amount of byte transferred
 	 *   by the faster flow
-	 * - check that the amount of queued data is greter than the above,
+	 * - check that the amount of queued data is greater than the above,
 	 *   otherwise do not use the picked, slower, subflow
 	 * We select the subflow with the shorter estimated time to flush
 	 * the queued mem, which basically ensure the above. We just need