kms_display_modes@extended-mode-basic failure

With the recent IGT tests in drm-ci we saw the below failure for msm,

msm-sc7180-trogdor-kingoftown: kms_display_modes@extended-mode-basic,Fail kms_display_modes@mst-extended-mode-negative,Fail

@lumag (Dmitry Baryshkov) analysed the issue and provided the below comments,

https://lore.kernel.org/dri-devel/f2dac4eatkajw633ksnnb3nfq7zop2l4ux2euj6jqg4hg3soqt@sv7p2r6xk7fz/

This is a bug in 5f7cde6a ("tests/kms_display_modes: Skip test if joiner display is connected"), the driver unconditionally calls is_joiner_mode(), or in 88abc2d2 ("lib/igt_kms: Add is_joiner_mode function"), the is_joiner_mode() should return false for non-Intel hardware. Please fix it in the IGT instead.

Logs: https://gitlab.freedesktop.org/vigneshraman/linux/-/jobs/67980315 https://gitlab.freedesktop.org/vigneshraman/linux/-/jobs/67980316