xrdb: simplify NetBSD-specific workaround

Author: 0-wiz-0

x11/xrdb/Makefile

@@ -1,4 +1,4 @@
-# $NetBSD: Makefile,v 1.13 2021/08/09 18:37:30 wiz Exp $
+# $NetBSD: Makefile,v 1.14 2022/08/30 18:42:53 wiz Exp $
 
 DISTNAME=		xrdb-1.2.1
 CATEGORIES=		x11
@@ -13,12 +13,7 @@ GNU_CONFIGURE=		yes
 USE_TOOLS+=		pkg-config
 
 CONFIGURE_ARGS+=	--with-cpp=${CPPPATH}
-
-.include "../../mk/bsd.prefs.mk"
-
-.if ${OPSYS} == "NetBSD"
-CONFIGURE_ARGS+=	ac_cv_func_reallocarray=no
-.endif
+CPPFLAGS.NetBSD+=	-D_OPENBSD_SOURCE
 
 .include "../../x11/libX11/buildlink3.mk"
 .include "../../x11/libXmu/buildlink3.mk"