drm/amd/display: switch amdgpu_dm_connector to use struct drm_edid

Replace raw edid handling (struct edid) with the opaque EDID type
(struct drm_edid) on amdgpu_dm_connector for consistency. It may also
prevent mismatch of approaches in different parts of the driver code.

Signed-off-by: Melissa Wen <mwen@igalia.com>
Co-developed-by: Mario Limonciello <mario.limonciello@amd.com>
Signed-off-by: Mario Limonciello <mario.limonciello@amd.com>
Reviewed-by: Alex Hung <alex.hung@amd.com>
Tested-by: Daniel Wheeler <daniel.wheeler@amd.com>
Signed-off-by: Rodrigo Siqueira <Rodrigo.Siqueira@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>