feat(plat/rcar3): use PRR cut to determine DRAM size on M3

The new M3 DRAM size can be determined by the PRR cut version.
Read the PRR cut version, and if it is older than cut 30, use
legacy DRAM size scheme, else report 8GB in 2GBx4 2ch split.

Signed-off-by: Toshiyuki Ogasahara <toshiyuki.ogasahara.bo@hitachi.com>
Signed-off-by: Yoshifumi Hosoya <yoshifumi.hosoya.wj@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com> # Fix DRAM size judgment by PRR register, reword commit message
Change-Id: Ib83176d0d09cab5cae0119ba462e42c66c642798
1 file changed