drm/radeon: set speakers allocation earlier

Do it before enabling audio channels (in AFMT_AUDIO_PACKET_CONTROL2
register).

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>

diff --cc drivers/gpu/drm/radeon/dce6_afmt.c
Simple merge

diff --cc drivers/gpu/drm/radeon/evergreen_hdmi.c
Simple merge