tests/bsim: Switch main return type from void to int

These changes were automated using coccinelle with the following
script:

@@
@@
- void
+ int
main(...) {
    ...
-	return;
+	return 0;
    ...
}

Signed-off-by: Keith Packard <keithp@keithp.com>

tests/bsim/bluetooth/host/adv/encrypted/css_sample_data/src/main.c

@@ -59,7 +59,8 @@ struct bst_test_list *test_encrypted_ad_data_install(struct bst_test_list *tests
 
 bst_test_install_t test_installers[] = {test_encrypted_ad_data_install, NULL};
 
-void main(void)
+int main(void)
 {
 	bst_main();
+	return 0;
 }

tests/bsim/bluetooth/host/gatt/settings/src/main.c

@@ -89,9 +89,10 @@ static struct bst_test_list *install(struct bst_test_list *tests)
 
 bst_test_install_t test_installers[] = { install, NULL };
 
-void main(void)
+int main(void)
 {
 	bst_main();
+	return 0;
 }
 
 

tests/bsim/bluetooth/host/privacy/central/src/main.c

@@ -33,7 +33,8 @@ static struct bst_test_list *install(struct bst_test_list *tests)
 
 bst_test_install_t test_installers[] = {install, NULL};
 
-void main(void)
+int main(void)
 {
 	bst_main();
+	return 0;
 }

tests/bsim/bluetooth/host/privacy/device/src/test_undirected_main.c

@@ -71,7 +71,8 @@ struct bst_test_list *test_privacy_install(struct bst_test_list *tests)
 
 bst_test_install_t test_installers[] = {test_privacy_install, NULL};
 
-void main(void)
+int main(void)
 {
 	bst_main();
+	return 0;
 }

tests/bsim/bluetooth/host/privacy/peripheral/src/main.c

@@ -33,7 +33,8 @@ static struct bst_test_list *install(struct bst_test_list *tests)
 
 bst_test_install_t test_installers[] = {install, NULL};
 
-void main(void)
+int main(void)
 {
 	bst_main();
+	return 0;
 }