include/linux/poison.h: remove obsolete comment

When the definition was changed, the comment became stale.  Just remove
it since there isn't anything useful to say here.

Fixes: b8a0255d ("include/linux/poison.h: use POISON_POINTER_DELTA for poison pointers")
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vasily Kulikov <segoon@openwall.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20200730174108.GJ23808@casper.infradead.orgSigned-off-by: Linus Torvalds <torvalds@linux-foundation.org>

include/linux/poison.h

@@ -24,10 +24,6 @@
 #define LIST_POISON2  ((void *) 0x122 + POISON_POINTER_DELTA)
 
 /********** include/linux/timer.h **********/
-/*
- * Magic number "tsta" to indicate a static timer initializer
- * for the object debugging code.
- */
 #define TIMER_ENTRY_STATIC	((void *) 0x300 + POISON_POINTER_DELTA)
 
 /********** mm/page_poison.c **********/