Use g_timeout_add_seconds() for power efficiency

This attempts to align second-granularity wakeups across the system,
reducing CPU wakeups a little.

I considered all timeouts of duration 1 second or greater, and moved
the non-timing-critical ones to g_timeout_add_seconds(). (Actually,
I didn't find any that I felt were timing-critical)

src/sugar/gsm-client-xsmp.c

@@ -110,7 +110,7 @@ gsm_client_xsmp_new (IceConn ice_conn)
 				   client_iochannel_watch, xsmp);
   g_io_channel_unref (channel);
 
-  xsmp->protocol_timeout = g_timeout_add (5000, client_protocol_timeout, xsmp);
+  xsmp->protocol_timeout = g_timeout_add_seconds (5, client_protocol_timeout, xsmp);
 
   set_description (xsmp);
   g_debug ("New client '%s'", xsmp->description);