drm/amd/display: Fix a switch statement in populate_dml_output_cfg_from_stream_state()

It is likely that the statement related to 'dml_edp' is misplaced. So move
it in the correct "case SIGNAL_TYPE_EDP".

Fixes: 7966f319 ("drm/amd/display: Introduce DML2")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Hamza Mahfooz <hamza.mahfooz@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@vger.kernel.org