ARM: shmobile: r8a7790: add internal PCI bridge nodes

Add device nodes for the R8A7790 internal PCI bridge devices.

Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Reviewed-by: Ian Molton <ian.molton@codethink.co.uk>
[Sergei: added several properties to the PCI bridge nodes]
Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Tested-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>