OMAP2,3: DSS2: Build omap_device for each DSS HWIP

Looks up the hwmod database for each of the given DSS HW IP and builds
omap_device which inturn does the platform device register for each of DSS HW IP

Signed-off-by: Senthilvadivu Guruswamy <svadivu@ti.com>
Signed-off-by: Sumit Semwal <sumit.semwal@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>