radeon/kms: force rn50 chip to always report connected on analog output

commit 51861d4eebc2ddc25c77084343d060fa79f6e291 upstream.

Those rn50 chip are often connected to console remoting hw and load
detection often fails with those. Just don't try to load detect and
report connect.

Signed-off-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>