arm64: dts: rockchip: Add enable-strobe-pulldown to emmc phy on ROCK Pi 4

arm64: dts: rockchip: Add enable-strobe-pulldown to emmc phy on ROCK Pi 4

Commit 8b5c2b45b8f0 disabled the internal pull-down for the strobe line
causing I/O errors in HS400 mode for various eMMC modules.

Enable the internal strobe pull-down for ROCK Pi 4 boards. Also re-enable
HS400 mode, that was replaced with HS200 mode as a workaround for the
stability issues in:
cee572756aa2 ("arm64: dts: rockchip: Disable HS400 for eMMC on ROCK Pi 4").

This was tested on ROCK 4SE and ROCK Pi 4B+.

Fixes: 8b5c2b45b8f0 ("phy: rockchip: set pulldown for strobe line in dts")
Signed-off-by: Folker Schwesinger <dev@folker-schwesinger.de>
Reviewed-by: Dragan Simic <dsimic@manjaro.org>
Link: https://lore.kernel.org/r/20240327192641.14220-2-dev@folker-schwesinger.de
Signed-off-by: Heiko Stuebner <heiko@sntech.de>