commit 57bcd0a6 upstream.

Missing check for crtcs present.

Fixes:
https://bugzilla.kernel.org/show_bug.cgi?id=193341
https://bugs.freedesktop.org/show_bug.cgi?id=99387Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>