docs: Fix path paste-o for /sys/kernel/warn_count

Running "make htmldocs" shows that "/sys/kernel/oops_count" was
duplicated. This should have been "warn_count":

  Warning: /sys/kernel/oops_count is defined 2 times:
  ./Documentation/ABI/testing/sysfs-kernel-warn_count:0
  ./Documentation/ABI/testing/sysfs-kernel-oops_count:0

Fix the typo.

Reported-by: kernel test robot <[email protected]>
Link: https://lore.kernel.org/linux-doc/[email protected]
Fixes: 8b05aa2 ("panic: Expose "warn_count" to sysfs")
Cc: [email protected]
Signed-off-by: Kees Cook <[email protected]>

Author: kees

Documentation/ABI/testing/sysfs-kernel-warn_count

@@ -1,4 +1,4 @@
-What:		/sys/kernel/oops_count
+What:		/sys/kernel/warn_count
 Date:		November 2022
 KernelVersion:	6.2.0
 Contact:	Linux Kernel Hardening List <[email protected]>