Fix FTBFS due to missing return values

kcontrol/background/KCrossBGRender.cc

@@ -221,6 +221,8 @@ bool KCrossBGRender::setCurrentEvent(bool init){
 			return true;
 		}
 	}
+
+	return false;
 }
 
 TQPixmap KCrossBGRender::getCurrentPixmap()

kcontrol/iccconfig/iccconfig.cpp

@@ -264,7 +264,7 @@ void KICCConfig::updateDisplayedInformation () {
 }
 
 TQString KICCConfig::extractFileName(TQString displayName, TQString profileName) {
-	//
+	return TQString();
 }
 
 int KICCConfig::findProfileIndex(TQString profileName) {

ksysguard/gui/kpm.c

@@ -4,5 +4,5 @@
 
 int main()
 {
-  return execlp( "ksysguard", "ksysguard", "--showprocesses", 0 );
+  return execlp( "ksysguard", "ksysguard", "--showprocesses", NULL );
 }