Fix processing of asterisk.conf debug=yes.

The code which reads asterisk.conf supports processing the debug
option with ast_true, but ast_true returns -1.  This causes debug
to still be off, convert to 1 so debug will be on as requested.

ASTERISK-25042
Reported by: Corey Farrell

Change-Id: I3c898b7d082d914b057e111b9357fde46bad9ed6

main/asterisk.c

@@ -3593,7 +3593,7 @@ static void ast_readconfig(void)
 		} else if (!strcasecmp(v->name, "debug")) {
 			option_debug = 0;
 			if (sscanf(v->value, "%30d", &option_debug) != 1) {
-				option_debug = ast_true(v->value);
+				option_debug = ast_true(v->value) ? 1 : 0;
 			}
 #if HAVE_WORKING_FORK
 		/* Disable forking (-f at startup) */