drm/vc4: Add 2712 support to vc4_plane_async_set_fb

vc4_plane_async_set_fb directly overwrites the plane address in
the dlist entry, but hadn't been updated for the GEN6 / 2712
dlist format, corrupting the address in the process.

Add support for the 2712 dlist format to the function.

Fixes: 1ab1fbbb ("drm/vc4: hvs: Support BCM2712 HVS")
Signed-off-by: Dave Stevenson <dave.stevenson@raspberrypi.com>