x86: kexec/i386: fix sparse warnings: Using plain integer as NULL pointer

Fix these sparse warnings:

  arch/x86/kernel/machine_kexec_32.c:124:22: warning: Using plain integer as NULL pointer
  arch/x86/kernel/traps.c:950:24: warning: Using plain integer as NULL pointer

Signed-off-by: Hannes Eder <hannes@hanneseder.net>
Cc: trivial@kernel.org
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index acb8c05..2df927b 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -942,7 +942,7 @@
 	info.si_signo = SIGILL;
 	info.si_errno = 0;
 	info.si_code = ILL_BADSTK;
-	info.si_addr = 0;
+	info.si_addr = NULL;
 	if (notify_die(DIE_TRAP, "iret exception",
 			regs, error_code, 32, SIGILL) == NOTIFY_STOP)
 		return;