Ensure that 'sysctl_hung_task_timeout_secs' is defined
even when CONFIG_DETECT_HUNG_TASK is not set.
This way we can safely reference it without need for
#ifdefs elsewhere in the code.  eg. in block/blk-exec.c

Signed-off-by: Mark Lord <mlord@pobox.com>

Jens: use the attachment.  My email client is having a fit today.

--- a/include/linux/sched.h	2010-09-20 19:56:53.000000000 -0400
+++ b/include/linux/sched.h	2010-09-24 17:22:01.707291995 -0400
@@ -336,6 +336,9 @@
  extern int proc_dohung_task_timeout_secs(struct ctl_table *table, int write,
  					 void __user *buffer,
  					 size_t *lenp, loff_t *ppos);
+#else
+/* Avoid need for ifdefs elsewhere in the code */
+enum { sysctl_hung_task_timeout_secs = 0 };
  #endif
  
  /* Attach to any functions which should be ignored in wchan output. */