Renamed ngx_handle_sent_chain() to ngx_chain_update_sent().

No functional changes.
diff --git a/src/os/unix/ngx_solaris_sendfilev_chain.c b/src/os/unix/ngx_solaris_sendfilev_chain.c
index 1b71f1d..e618379 100644
--- a/src/os/unix/ngx_solaris_sendfilev_chain.c
+++ b/src/os/unix/ngx_solaris_sendfilev_chain.c
@@ -197,7 +197,7 @@
 
         c->sent += sent;
 
-        in = ngx_handle_sent_chain(in, sent);
+        in = ngx_chain_update_sent(in, sent);
 
         if (eintr) {
             send = prev_send + sent;