ARM: shmobile: r8a7740/armadillo legacy: Add A4MP pm domain support

Add support for the A4MP power domain, and hook up the HDMI-Link and FSI
hardware blocks.
This domain also contains the SPU2, FMSI, and BBIF2 hardware blocks,
but these are currently not used by any driver.

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Simon Horman <horms+renesas@verge.net.au>