kconfig: do not hardcode ".config" filename

Rather than hardcoding ".config" use conf_get_configname(), which also
respects the environment variable KCONFIG_CONFIG.

This fixes "make silentoldconfig" when KCONFIG_CONFIG is used and also
suggests the given filename for "Load" and "Save as" in qconf.
Signed-off-by: Markus Heidelberg <markus.heidelberg@web.de>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

scripts/kconfig/conf.c

@@ -498,14 +498,15 @@ int main(int ac, char **av)
 	conf_parse(name);
 	//zconfdump(stdout);
 	if (sync_kconfig) {
-		if (stat(".config", &tmpstat)) {
+		name = conf_get_configname();
+		if (stat(name, &tmpstat)) {
 			fprintf(stderr, _("***\n"
 				"*** You have not yet configured your kernel!\n"
-				"*** (missing kernel .config file)\n"
+				"*** (missing kernel config file \"%s\")\n"
 				"***\n"
 				"*** Please run some configurator (e.g. \"make oldconfig\" or\n"
 				"*** \"make menuconfig\" or \"make xconfig\").\n"
-				"***\n"));
+				"***\n"), name);
 			exit(1);
 		}
 	}

scripts/kconfig/qconf.cc

@@ -1448,7 +1448,7 @@ ConfigMainWindow::ConfigMainWindow(void)
 
 void ConfigMainWindow::loadConfig(void)
 {
-	QString s = QFileDialog::getOpenFileName(".config", NULL, this);
+	QString s = QFileDialog::getOpenFileName(conf_get_configname(), NULL, this);
 	if (s.isNull())
 		return;
 	if (conf_read(QFile::encodeName(s)))
@@ -1464,7 +1464,7 @@ void ConfigMainWindow::saveConfig(void)
 
 void ConfigMainWindow::saveConfigAs(void)
 {
-	QString s = QFileDialog::getSaveFileName(".config", NULL, this);
+	QString s = QFileDialog::getSaveFileName(conf_get_configname(), NULL, this);
 	if (s.isNull())
 		return;
 	if (conf_write(QFile::encodeName(s)))