MdePkg/DxeServicesLib: remove bogus cast

MdePkg/DxeServicesLib: remove bogus cast

The HandleProtocol() boot service takes an EFI_HANDLE, not an
(EFI_HANDLE*). Remove the bogus cast in the
InternalImageHandleToFvHandle() function.

This is a semantic cleanup; there is no change in behavior.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Signed-off-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
Reviewed-by: Philippe Mathieu-Daude <philmd@redhat.com>