Revert "drm/radeon: dont switch vt on suspend"

commit 18c437ca upstream.

Fixes distorted colors on some cards on resume from suspend.

This reverts commit b9729b17.

Bug: https://bugs.freedesktop.org/show_bug.cgi?id=98832
Bug: https://bugs.freedesktop.org/show_bug.cgi?id=99163
Bug: https://bugzilla.kernel.org/show_bug.cgi?id=107001


Reviewed-by: Michel Dänzer <michel.daenzer@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>