payloads/libpayload: Don't use old style function definition

Use "int foo(void)" instead of old-style "int foo()".

Change-Id: Ic698dbbba74d579a21ff57005a7aa9bb8ce80253
Signed-off-by: Elyes Haouas <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/77485
Reviewed-by: Eric Lai <eric_lai@quanta.corp-partner.google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

payloads/libpayload/curses/PDCurses/doc/manext.c

@@ -30,7 +30,7 @@
 
 #define MAX_LINE 255
 
-void display_info()
+void display_info(void)
 {
     fprintf(stderr, "\nMANEXT 1.03 Copyright (C) 1991-1996 Mark Hessling\n"
                     "All rights reserved.\n"