rbutil: Fix sansapatcher bootloader install on Windows.

During bootloader installation sansapatcher disk access is accidentially
set up twice. This is not a problem except on Windows, which will abort
with a "permission denied" error.

This is basically the same problem as for ipodpatcher bootloader install.

Change-Id: I03220e17d0e00a15fff23c02aba7da93d4781964

utils/rbutilqt/base/bootloaderinstallipod.cpp

@@ -29,6 +29,11 @@ BootloaderInstallIpod::BootloaderInstallIpod(QObject *parent)
         : BootloaderInstallBase(parent)
 {
     ipod.sectorbuf = nullptr;
+#if defined(Q_OS_WIN32)
+    ipod.dh = INVALID_HANDLE_VALUE;
+#else
+    ipod.dh = -1;
+#endif
 }