Unix: cache the password used for mounting

Reuse the prepared password to avoid rereading outer keyfiles after
mounting. This prevents post-mount read failures and ensures the cache
contains the credential that unlocked the volume.

src/Core/Unix/CoreServiceProxy.h

@@ -170,7 +170,7 @@ namespace VeraCrypt
 			if (!useCachedPasswords && options.CachePassword
 				&& ((options.Password && !options.Password->IsEmpty()) || (options.Keyfiles && !options.Keyfiles->empty())))
 			{
-				VolumePasswordCache::Store (*Keyfile::ApplyListToPassword (options.Keyfiles, options.Password, options.EMVSupportEnabled));
+				VolumePasswordCache::Store (*newOptions.Password);
 			}
 
 			VolumeEventArgs eventArgs (mountedVolume);