ARM: shmobile: porter: enable SATA0

Enable SATA0 device for the Porter board.

This patch is analogous to the commit 5a62ec57

 ("ARM: shmobile:
henninger: enable SATA0") as there are no differences between the boards
in this respect.

Signed-off-by: Sergei Shtylyov <sergei.shtylyov@cogentembedded.com>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>