fault-injection: make some stack filter attrs more readable

Attributes of stack filter are show as unsigned decimal, such as
'require-start', 'require-end'.  This patch change to show them as
unsigned hexadecimal for more readable.

Before:
  $ echo 0xffffffffc0257000 > /sys/kernel/debug/failslab/require-start
  $ cat /sys/kernel/debug/failslab/require-start
  18446744072638263296

After:
  $ echo 0xffffffffc0257000 > /sys/kernel/debug/failslab/require-start
  $ cat /sys/kernel/debug/failslab/require-start
  0xffffffffc0257000

[wangyufen@huawei.com: use debugfs_create_xul() instead of debugfs_create_xl()]
  Link: https://lkml.kernel.org/r/1664331299-4976-1-git-send-email-wangyufen@huawei.com
Link: https://lkml.kernel.org/r/20220817080332.10527106

-4-weiyongjun1@huawei.com
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Wang Yufen <wangyufen@huawei.com>
Reviewed-by: Akinobu Mita <akinobu.mita@gmail.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Isabella Basso <isabbasso@riseup.net>
Cc: Josh Poimboeuf <jpoimboe@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Miguel Ojeda <ojeda@kernel.org>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>