rockchip: rk356x-u-boot: Add bootph-all to common pinctrl nodes

Add bootph-all prop to common pinctrl nodes for eMMC, FSPI, SD-card and
UART2 that are typically used by multiple boards. Unreferenced nodes are
removed from the SPL device tree during a normal build.

Signed-off-by: Jonas Karlman <jonas@kwiboo.se>
Reviewed-by: Kever Yang <kever.yang@rock-chips.com>