ipmi/watchdog: use nmi_panic() when kernel panics in NMI handler

Commit 1717f209 ("panic, x86: Fix re-entrance problem due to panic
on NMI") introduced nmi_panic() which prevents concurrent and recursive
execution of panic().  It also saves registers for the crash dump on x86
by later commit 58c5661f ("panic, x86: Allow CPUs to save registers
even if looping in NMI context").

ipmi_watchdog driver can call panic() from NMI handler, so replace it
with nmi_panic().
Signed-off-by: NHidehiro Kawai <hidehiro.kawai.ez@hitachi.com>
Acked-by: NCorey Minyard <cminyard@mvista.com>
Acked-by: NGuenter Roeck <linux@roeck-us.net>
Reviewed-by: NMichal Hocko <mhocko@suse.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

drivers/char/ipmi/ipmi_watchdog.c

@@ -1140,7 +1140,7 @@ ipmi_nmi(unsigned int val, struct pt_regs *regs)
 		   the timer.   So do so. */
 		pretimeout_since_last_heartbeat = 1;
 		if (atomic_inc_and_test(&preop_panic_excl))
-			panic(PFX "pre-timeout");
+			nmi_panic(regs, PFX "pre-timeout");
 	}
 
 	return NMI_HANDLED;