The DDRTYPE defines are named to be RK3399 specific, but they can be
used for other Rockchip SoCs as well, so replace the RK3399_PMUGRF_
prefix with ROCKCHIP_. They are defined in a SoC specific header
file, so when generalizing the prefix also move the new defines to
a SoC agnostic header file. While at it use GENMASK to define the
DDRTYPE bitfield and give it a name including the full register name.

Link: https://lore.kernel.org/all/20231018061714.3553817-9-s.hauer@pengutronix.de/Reviewed-by: Sebastian Reichel <sebastian.reichel@collabora.com>
Acked-by: Chanwoo Choi <cw00.choi@samsung.com>
Acked-by: Heiko Stuebner <heiko@sntech.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>