staging: unisys: change pr_err to dev_err in visor_check_channel

Changing pr_err to dev_err in visor_check_channel. Added device
as an argument to visor_check_channel to pass into dev_err.

Signed-off-by: Sameer Wadgaonkar <sameer.wadgaonkar@unisys.com>
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>