s390/nmi: Annotate s390_handle_damage() with __noreturn

s390_handle_damage() ends by calling the non-returning function
disabled_wait() and therefore also never returns. Annotate it with the
__noreturn compiler attribute to improve compiler optimizations.

Remove the unreachable infinite while loop.

Signed-off-by: Thorsten Blum <[e-mail]>
Signed-off-by: Heiko Carstens <[e-mail]>

arch/s390/kernel/nmi.c

···
 	sclp_emergency_printk(message);
 }
 
-static notrace void s390_handle_damage(void)
+static notrace void __noreturn s390_handle_damage(void)
 {
 	struct lowcore *lc = get_lowcore();
 	union ctlreg0 cr0, cr0_new;
···
 	lc->mcck_new_psw = psw_save;
 	local_ctl_load(0, &cr0.reg);
 	disabled_wait();
-	while (1);
 }
 NOKPROBE_SYMBOL(s390_handle_damage);