staging: unisys: simplify controlvm channel address function

There is no reason to have controlvm_get_channel_address() defined in a
separate file. Move it to visorchipset_main.c, remove the no-op functions
controlvm_init() and controlvm_deinit() from visorchipset_main.c, and remove
the controlvm.h and controlvm_direct.c files from the module.

Signed-off-by: Benjamin Romer <benjamin.romer@unisys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>