Use pkgconfig for localization of libcrypto. This is needed for tests in
multilib systems.

diff --git a/extra/engine/GNUmakefile b/extra/engine/GNUmakefile
index b50717b..3712ad6 100644
--- a/extra/engine/GNUmakefile
+++ b/extra/engine/GNUmakefile
@@ -16,9 +16,9 @@ else
 SUFFIX:=	so
 endif
 
-CFLAGS+=	-fPIC -I$(OPENSSL_BASE)/include
-LDFLAGS+=	-L$(OPENSSL_BASE)/lib
-LIBS+=		-lcrypto
+CFLAGS+=	-fPIC $(shell pkg-config --cflags libcrypto)
+LDFLAGS+=	$(shell pkg-config --libs-only-L libcrypto)
+LIBS+=		$(shell pkg-config --libs-only-l libcrypto)
 
 TARGET=		dummy-engine
 
-- 
2.35.1