m68k{nommu}: Remove unused DEFINE's from asm-offsets.c

m68k{nommu}/asm-offsets.c define many constants which are not used
anymore anywhere; remove IRQ_DEVID, IRQ_HANDLER, IRQ_NEXT, STAT_IRQ,
TASK_ACTIVE_MM, TASK_BLOCKED, TASK_FLAGS, TASK_PTRACE, TASK_STATE,
TASK_THREAD_INFO, TI_CPU, TI_EXECDOMAIN and TI_TASK.

Signed-off-by: Philippe De Muyter <phdm@macqel.be>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>