Use the shlib wrapper when running nptest

Since there seems to be no way to avoid linking to libssl and libcrypto,
just wrap the test. This unbreaks "shared" builds when using clang and/or
OS X.
Signed-off-by: NRich Salz <rsalz@openssl.org>
Reviewed-by: NBen Laurie <ben@openssl.org>

test/Makefile

@@ -173,7 +173,7 @@ alltests: \
 
 test_np: $(NPTEST)$(EXE_EXT)
 	@echo $(START) $@
-	./$(NPTEST)
+	../util/shlib_wrap.sh ./$(NPTEST)
 
 test_evp: $(EVPTEST)$(EXE_EXT) evptests.txt
 	@echo $(START) $@