staging: unisys: visorbus: vbuschannel doesn't use ctypes

Don't include ctypes in vbuschannel.h, it isn't used by ctypes, but it is
used by visorbus_main.c so include it there.

Signed-off-by: David Kershner <david.kershner@unisys.com>
Reviewed-by: Tim Sell <timothy.sell@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>