address win32 build issues

- Replace external -DOPENSSL/-DPKCS11CRYPTO with properly AC_DEFINEd
  HAVE_OPENSSL/HAVE_PKCS11
- Don't enforce the crypto provider from platform.h, just from dst_api.c
  and configure scripts

bin/tests/virtual-time/vtwrapper.c

@@ -9,6 +9,7 @@
  * information regarding copyright ownership.
  */
 
+#include <config.h>
 
 #define _GNU_SOURCE
 #include <sys/syscall.h>