Revert "x86: Fix __get_wchan() for !STACKTRACE"

Revert "x86: Fix __get_wchan() for !STACKTRACE"

This reverts commit e1ff40b6194f09c1dd0f45b94fdf30c0374b5823 which is
commit 5d1ceb3969b6b2e47e2df6d17790a7c5a20fcbb4 upstream.

It has been reported to be causing problems, and is being reworked
upstream and has been dropped from the current 5.15.y stable queue until
it gets resolved.

Reported-by: Chris Rankin <rankincj@gmail.com>
Reported-by: Thorsten Leemhuis <linux@leemhuis.info>
Link: https://lore.kernel.org/r/ed000478-2a60-0066-c337-a04bffc112b1@leemhuis.info
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>