Now that the driver core can properly handle constant struct bus_type,
move the hv_bus variable to be a constant structure as well,
placing it into read-only memory which can not be modified at runtime.

Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Suggested-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ricardo B. Marliere <ricardo@marliere.net>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Michael Kelley <mhklinux@outlook.com>
Link: https://lore.kernel.org/r/20240204-bus_cleanup-hv-v1-1-521bd4140673@marliere.netSigned-off-by: Wei Liu <wei.liu@kernel.org>
Message-ID: <20240204-bus_cleanup-hv-v1-1-521bd4140673@marliere.net>