Tune diagnostic logging that happens during mce startup

Running "mce -Tv" from command line should not show insignificant info.

Demote non-interesting diagnostic to INFO level.

Avoid emitting warnings about illegal display state requests that
happen due to request filtering.

builtin-gconf.c

@@ -1576,7 +1576,7 @@ static void gconf_client_save_values(GConfClient *self, const char *path)
   size_t  size = 0;
   FILE   *file = 0;
 
-  mce_log(LL_NOTICE, "updating %s", path);
+  mce_log(LL_INFO, "updating %s", path);
 
   if( !(file = open_memstream(&data, &size)) ) {
     goto cleanup;

mce-io.c

@@ -351,7 +351,7 @@ static mce_io_mon_t *mce_io_mon_create(const char *path, mce_io_mon_delete_cb de
 	self->user_data     = 0;
 	self->user_free_cb  = 0;
 
-	mce_log(LL_NOTICE, "adding monitor for: %s", self->path);
+	mce_log(LL_DEBUG, "adding monitor for: %s", self->path);
 
 EXIT:
 	return self;

modules/display.c

@@ -1229,6 +1229,13 @@ static void mdy_datapipe_display_state_req_cb(gconstpointer data)
     case MCE_DISPLAY_POWER_UP:
     case MCE_DISPLAY_POWER_DOWN:
         /* Ignore transient or otherwise invalid display states */
+
+        /* Any "no-change" transient state requests practically
+         * have to be side effects of display state request
+         * filtering - no need to make fuzz about them */
+        if( next_state == display_state )
+            break;
+
         mce_log(LL_WARN, "%s is not valid target state; ignoring",
                 mdy_display_state_name(next_state));
         break;
@@ -6291,7 +6298,7 @@ static governor_setting_t *mdy_governor_get_settings(const char *tag)
     snprintf(sec, sizeof sec, "CPUScalingGovernor%s", tag);
 
     if( !mce_conf_has_group(sec) ) {
-        mce_log(LL_NOTICE, "Not configured: %s", sec);
+        mce_log(LL_INFO, "Not configured: %s", sec);
         goto EXIT;
     }