Respect LDFLAGS & fix configure check for libobjc2

clang from ports did pass -L/usr/local/lib to the linker, gcc or clang
from base don't do that, so fix detection.  Note that "gcc" is used at
configure time if available, even if the actual build uses "cc".

Maintainer timeout.

net/openvpn-auth-ldap/Makefile

@@ -1,4 +1,4 @@
-# $OpenBSD: Makefile,v 1.13 2017/07/27 09:55:45 sthen Exp $
+# $OpenBSD: Makefile,v 1.14 2017/08/03 14:46:33 jca Exp $
 
 COMMENT =		LDAP authentication plugin for OpenVPN 2.x
 
@@ -35,10 +35,11 @@ AUTOCONF_VERSION =	2.69
 CONFIGURE_STYLE =	autoconf
 MAKE_FILE =		Makefile
 
-CONFIGURE_ARGS += --prefix=${LOCALBASE} \
-		  --with-check=${LOCALBASE} \
+CONFIGURE_ARGS =  --with-check=${LOCALBASE} \
 		  --with-openldap=${LOCALBASE} \
 		  --with-openvpn=${LOCALBASE}/include/openvpn
+CONFIGURE_ENV =		CPPFLAGS="-I${LOCALBASE}/include" \
+			LDFLAGS="-L${LOCALBASE}/lib ${LDFLAGS}"
 
 SAMPLES_DIR =		${PREFIX}/share/examples/openvpn-auth-ldap
 

net/openvpn-auth-ldap/patches/patch-platform_m4

@@ -0,0 +1,16 @@
+$OpenBSD: patch-platform_m4,v 1.1 2017/08/03 14:46:33 jca Exp $
+
+Don't clobber LDFLAGS.
+
+Index: platform.m4
+--- platform.m4.orig
++++ platform.m4
+@@ -97,7 +97,7 @@ AC_DEFUN(OD_CONFIG_PLUGIN, [
+ 	    PLUGIN_LD="${CC} -shared"
+ 	    PLUGIN_LD_FLAGS=""
+ 	    PLUGIN_SUFFIX=".so"
+-	    LDFLAGS="-export-dynamic"
++	    LDFLAGS="-export-dynamic ${LDFLAGS}"
+ 	    ;;
+     esac
+