Revert "drm/amdgpu: install stub fence into potential unused fence pointers"

Revert "drm/amdgpu: install stub fence into potential unused fence pointers"

This reverts commit 04bd3a362d2f1788272776bd8b10e5a012e69b77 which is
commit 187916e6ed9d0c3b3abc27429f7a5f8c936bd1f0 upstream.

It is reported to cause lots of log spam, so it should be dropped for
now.

Reported-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/27d08b24-3581-4451-b8db-5df144784d6a@roeck-us.net
Reported-by: From: Chia-I Wu <olvaffe@gmail.com>
Link: https://lore.kernel.org/r/CAPaKu7RTgAMBLHbwtp4zgiBSDrTFtAj07k5qMzkuLQy2Zr+sZA@mail.gmail.com
Cc: Christian König <christian.koenig@amd.com>
Cc: Lang Yu <Lang.Yu@amd.com>
Cc: Alex Deucher <alexander.deucher@amd.com>
Cc: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>