libgnt/libgnt

Remove C99-obsoleted constructs

19 months ago, Elliott Sales de Andrade
f5126e6837e3
Remove C99-obsoleted constructs

See [this development thread for a future Fedora change](https://lists.fedoraproject.org/archives/list/devel@lists.fedoraproject.org/thread/CJXKTLXJUPZ4F2C2VQOTNMEA5JAUPMBD/) or [the proposed change page](https://fedoraproject.org/wiki/Changes/PortingToModernC). These may be made stronger errors in GCC 14.

Testing Done:
Configured with `-Dc_args='-Werror=implicit-int -Werror=implicit-function-declaration -Werror=int-conversion -Werror=strict-prototypes -Werror=old-style-definition'` and compiled.

Reviewed at https://reviews.imfreedom.org/r/1973/
#include <gnt.h>
int
main(void)
{
GntWidget *win, *button;
gnt_init();
gnt_util_parse_widgets("<vwindow id='0' fill='0' align='2'><label>This is a test.</label><button id='1'>OK</button></vwindow>", 2, &win, &button);
g_signal_connect_swapped(G_OBJECT(button), "activate", G_CALLBACK(gnt_widget_destroy), win);
gnt_widget_show(win);
gnt_main();
gnt_quit();
return 0;
}