Convert the code to allow per-device probe() like other device drivers.
This also delays driver registration due to change from subsys_initcall()
to regular module_platform_driver().
Signed-off-by: Magnus Damm <damm@opensource.se> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com> Acked-by: Simon Horman <horms+renesas@verge.net.au>