[Why]
When running igt@kms_plane@pixel-format-pipe-* tests the CRC read will
time out and the test will fail.

This is because the CRTC is duplicated but the crc_enabled parameter
isn't copied over to the new dm_crtc_state. CRC reads will time out
because amdgpu_dm_crtc_handle_crc_irq will no longer call
drm_crtc_add_crc_entry.

[How]
Copy crc_enabled when duplicating the state.
Signed-off-by: Nicholas Kazlauskas <nicholas.kazlauskas@amd.com>
Reviewed-by: David Francis <David.Francis@amd.com>
Reviewed-by: Sun peng Li <Sunpeng.Li@amd.com>
Acked-by: Leo Li <sunpeng.li@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>