tests/kms_plane_multiple: Drain pipe before reading CRC

In CI runs we every now and then fail to read correct CRC yielding an error
when comparing reference and grabbed CRC's. Let's first fix the test so that
we drain the pipe first and then read the correct CRC. While at it, let's
simplify the test by combining legacy and atomic tests into a one common
function.

v2: We don't need to drain pipe when we grab first CRC
v3: Nuke legacy commits

References: https://bugs.freedesktop.org/show_bug.cgi?id=103166
Signed-off-by: Mika Kahola <mika.kahola@intel.com>
Reviewed-by: Arkadiusz Hiler <arkadiusz.hiler@intel.com>

0 files changed, 0 insertions, 0 deletions