ARM: davinci: da8xx: Fix ohci device name

While the clk lookup table is making reference to "ohci"
other subsystems (such as phy) are trying to match "ohci.0"

Since there is a single ohci instance, instead of changing
the clk name, change the dev id to -1, and add the "-da8xx"
postfix to match the driver name that will also be changed
in a subsequent patch.

Signed-off-by: Axel Haslam <ahaslam@baylibre.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>