ARM: davinci: da8xx: Add names to DSP IOMEM resources

Add names to the IOMEM resources for the DSP device present on
DA8xx SoCs. This will facilitate the driver to use the names and
be agnostic of the resource order, and facilitate scalable DT
support in follow-up patches.

Signed-off-by: Suman Anna <s-anna@ti.com>
Signed-off-by: Sekhar Nori <nsekhar@ti.com>