pata_octeon_cf: use of_property_read_{bool|u32}()

The Octeon CF driver basically  open-codes of_property_read_{bool|u32}()
using  of_{find|get}_property() calls in its  probe() method.  Using the
modern DT APIs saves 2 LoCs and 16 bytes of object code (MIPS gcc 3.4.3).

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Tejun Heo <tj@kernel.org>