tty: serial: jsm: remove redundant assignments to variable linestatus

tty: serial: jsm: remove redundant assignments to variable linestatus

Variable linestatus is being assigned values that are never read, the
assignments are redundant and can be removed.

Cleans up clang scan warnings:
drivers/tty/serial/jsm/jsm_cls.c:369:2: warning: Value stored to
'linestatus' is never read [deadcode.DeadStores]
drivers/tty/serial/jsm/jsm_cls.c:400:4: warning: Value stored to
'linestatus' is never read [deadcode.DeadStores]

Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20220307153047.139639-1-colin.i.king@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>