Remove the ADJUST_CLOCK ioctl on pc98. It's not used at all.

sys/dev/syscons/syscons.c

@@ -1340,12 +1340,6 @@ scioctl(struct cdev *dev, u_long cmd, caddr_t data, int flag, struct thread *td)
 
 #endif /* SC_NO_FONT_LOADING */
 
-#ifdef PC98
-    case ADJUST_CLOCK:	/* /dev/rtc for 98note resume */
-	inittodr(0);
-	return 0;
-#endif
-
     default:
 	break;
     }

sys/sys/consio.h

@@ -290,10 +290,6 @@ typedef struct term_info term_info_t;
 #define CONS_GETTERM	_IOWR('c', 112, term_info_t)
 #define CONS_SETTERM	_IOW('c', 113, term_info_t)
 
-#ifdef PC98
-#define ADJUST_CLOCK	_IO('t',100)		/* for 98note resume */
-#endif
-
 /*
  * Vty switching ioctl commands.
  */