drm/amd/display: Fix incorrect dcn1 bandwidth calculations

[WHY]
Typos cause bandwidth calculation errors, one
of which can cause infinite loop on dcn1 with eDP

Signed-off-by: Michael Strauss <michael.strauss@amd.com>
Reviewed-by: Dmytro Laktyushkin <Dmytro.Laktyushkin@amd.com>
Acked-by: Qingqing Zhuo <qingqing.zhuo@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>