Add a method for checking if ZSTD was compiled with flags that impact determinism

lib/common/zstd_common.c

@@ -46,3 +46,12 @@ ZSTD_ErrorCode ZSTD_getErrorCode(size_t code) { return ERR_getErrorCode(code); }
 /*! ZSTD_getErrorString() :
  *  provides error code string from enum */
 const char* ZSTD_getErrorString(ZSTD_ErrorCode code) { return ERR_getErrorString(code); }
+
+int ZSTD_isDeterministicBuild(void)
+{
+#if ZSTD_IS_DETERMINISTIC_BUILD
+    return 1;
+#else
+    return 0;
+#endif
+}