sh-pfc: Consolidate PFC SoC data macros

Move macros defined in several SoC data files to a common location and
document them.

Signed-off-by: Laurent Pinchart <laurent.pinchart+renesas@ideasonboard.com>
Tested-by: Yusuke Goda <yusuke.goda.sx@renesas.com>
9 files changed