imx9: imx93_evk: add low drive mode support on 11x11 EVK

Add a static u-boot config for i.MX93 low drive mode support. When
low drive mode is enabled, VDD_SOC is set to 0.75V. Bus clocks,
A55 core clock (900Mhz), DDR clock (1866MTS), and some peripherals
clocks (USDHC/FLEXSPI/PDM/DISP_PIX/CAM_PIX) must decrease to meet
max frequencies in low drive mode.

Also set standby voltage for buck1

Signed-off-by: Ye Li <ye.li@nxp.com>
Signed-off-by: Peng Fan <peng.fan@nxp.com>
diff --git a/board/freescale/imx93_evk/Makefile b/board/freescale/imx93_evk/Makefile
index 575f8e9..17956d2 100644
--- a/board/freescale/imx93_evk/Makefile
+++ b/board/freescale/imx93_evk/Makefile
@@ -8,5 +8,9 @@
 
 ifdef CONFIG_SPL_BUILD
 obj-y += spl.o
+ifdef CONFIG_IMX9_LOW_DRIVE_MODE
+obj-$(CONFIG_IMX93_EVK_LPDDR4X) += lpddr4x_timing_ld.o
+else
 obj-$(CONFIG_IMX93_EVK_LPDDR4X) += lpddr4x_timing.o
 endif
+endif