drm/amd/display: force toggle rate wa for first link training for a retimer

stable inclusion
from stable-v6.6.5
commit a29a8e06dc8e7f95f97de112ef43c53cdc1a72cd
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I8N21P

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=a29a8e06dc8e7f95f97de112ef43c53cdc1a72cd



--------------------------------

commit eb28018943fed7639dfea1c9ec9c756ec692b99a upstream.

[WHY]
Handover from DMUB to driver does not perform link rate toggle.
It might cause link training failure for boot up.

[HOW]
Force toggle rate wa for first link train.
link->vendor_specific_lttpr_link_rate_wa should be zero then.

Cc: stable@vger.kernel.org # 6.1+
Reviewed-by: Michael Strauss <michael.strauss@amd.com>
Acked-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Zhongwei <zhongwei.zhang@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Zheng Zengkai <zhengzengkai@huawei.com>