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>

arch/xtensa/platforms/iss/console.c

@@ -28,10 +28,6 @@
 #include <linux/tty.h>
 #include <linux/tty_flip.h>
 
-#ifdef SERIAL_INLINE
-#define _INLINE_ inline
-#endif
-
 #define SERIAL_MAX_NUM_LINES 1
 #define SERIAL_TIMER_VALUE (HZ / 10)