staging: unisys: visorbus: move bus_device_info_init to visorbus_main.c

The function bus_device_info_init was defined in visorbus_private.h. The
only file that uses it is visorbus_main.c so move the function into the .c
file instead.

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