Windows: Add option to enable use of CPU RDRAND/RDSEED as source of entropy which is now disabled by default

src/Common/Crypto.h

@@ -385,6 +385,10 @@ BOOL IsAesHwCpuSupported ();
 void EnableHwEncryption (BOOL enable);
 BOOL IsHwEncryptionEnabled ();
 
+BOOL IsCpuRngSupport ();
+void EnableCpuRng (BOOL enable);
+BOOL IsCpuRngEnabled ();
+
 #ifdef __cplusplus
 }
 #endif