Fix kernel/softirq.c printk format warning properly

This fixes the broken 77af7e3403
("softirq, warning fix: correct a format to avoid a warning") fix
correctly.

The type of a pointer subtraction is not "int", nor is it "long".  It
can be either (or something else).  It's "ptrdiff_t", and the printk
format for it is "%td".

Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

kernel/softirq.c

@@ -210,7 +210,7 @@ restart:
 			h->action(h);
 
 			if (unlikely(prev_count != preempt_count())) {
-				printk(KERN_ERR "huh, entered softirq %d %p"
+				printk(KERN_ERR "huh, entered softirq %td %p"
 				       "with preempt_count %08x,"
 				       " exited with %08x?\n", h - softirq_vec,
 				       h->action, prev_count, preempt_count());