info: Fix incompatible pointer type

This fixes the following:
```
libfreerdp/core/info.c: In function ‘rdp_read_info_null_string’:
libfreerdp/core/info.c:88:39: error: initialization of ‘const WCHAR *’ {aka ‘const short unsigned int *’} from incompatible pointer type ‘BYTE *’ {aka ‘unsigned char *’} [-Wincompatible-pointer-types]
   88 |                 const WCHAR* domain = Stream_Pointer(s);
```

libfreerdp/core/info.c

@@ -85,7 +85,7 @@ static BOOL rdp_read_info_null_string(const char* what, UINT32 flags, wStream* s
 
 	if (cbLen > 0)
 	{
-		const WCHAR* domain = Stream_Pointer(s);
+		const WCHAR* domain = (WCHAR*)Stream_Pointer(s);
 
 		if (isNullTerminated && (max > 0))
 			max -= nullSize;