tty: hvc: remove set but unused variable

The local variable vdev in hvcs_destruct_port() is set
but not used. Remove the variable and related code.

Signed-off-by: Bo Liu <liubo03@inspur.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Link: https://lore.kernel.org/r/20230908061726.2641-1-liubo03@inspur.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>