Fix printf in first party test (#970)

fix #944 

Passing va to ... is invalid, but I didn't find an offical doc

Author: trdthg

test/first_party/src/common/runtime.c

@@ -6,7 +6,7 @@ int printf(const char *fmt, ...)
 {
   va_list ap;
   va_start(ap, fmt);
-  int rc = npf_pprintf(&htif_putc, NULL, fmt, ap);
+  int rc = npf_vpprintf(&htif_putc, NULL, fmt, ap);
   va_end(ap);
   return rc;
 }