TTY: xtensa/iss/console, remove unused _INLINE_ definition

This is a remnant from the dark age. Nobody uses the macro now, so
remove.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Chris Zankel <chris@zankel.net>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: <linux-xtensa@linux-xtensa.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>