Fix documentation of sysrq-q

I fell into the trap recently that it only dumps hrtimers instead of
all timers. Fix the documentation.

Signed-off-by: Andi Kleen <ak@linux.intel.com>
Cc: torvalds@linux-foundation.org
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

Documentation/sysrq.txt

@@ -95,7 +95,8 @@ On all -  write a character to /proc/sysrq-trigger.  e.g.:
 
 'p'     - Will dump the current registers and flags to your console.
 
-'q'     - Will dump a list of all running timers.
+'q'     - Will dump a list of all running hrtimers.
+	  WARNING: Does not cover any other timers
 
 'r'     - Turns off keyboard raw mode and sets it to XLATE.