rockchip: sdram: Fix register layout for Linux

rockchip: sdram: Fix register layout for Linux

The ChromeOS kernel reads the RAM settings from PMU_SYS_REG2 and expects
the bootloader to store the necessary information there.  We're using
the same register to pass the same information between the SPL and
U-Boot but in a slightly different format.

Change this to use the format expected by the Linux DMC driver so that
the system doesn't hang in Linux by misconfiguring the RAM.

This is almost the same as commit b5788dc ("rockchip: rk3288: correct
sdram setting") which was reverted in commit b525556 ("Revert "rockchip:
rk3288: correct sdram setting"") but parenthese have been added to apply
the mask correctly when reading the "bw" setting and a couple of minor
style issues have been fixed to keep check_patch.pl happy.

Signed-off-by: John Keeping <john@metanate.com>
Reviewed-by: Tom Rini <trini@konsulko.com>
Acked-by: Simon Glass <sjg@chromium.org>