feat(stm32mp2): handle DDR power supplies

Modify platform driver to handle the DDR power supplies when
a PMIC is present.

Signed-off-by: Pascal Paillet <p.paillet@st.com>
Change-Id: I98df132a63c2ad351d4dae949f5dbb831cc40637
diff --git a/plat/st/stm32mp2/platform.mk b/plat/st/stm32mp2/platform.mk
index a22fe5c..7002e5e 100644
--- a/plat/st/stm32mp2/platform.mk
+++ b/plat/st/stm32mp2/platform.mk
@@ -126,7 +126,8 @@
 
 BL2_SOURCES			+=	plat/st/stm32mp2/plat_bl2_mem_params_desc.c
 
-BL2_SOURCES			+=	plat/st/stm32mp2/bl2_plat_setup.c
+BL2_SOURCES			+=	plat/st/stm32mp2/bl2_plat_setup.c			\
+					plat/st/stm32mp2/plat_ddr.c
 
 ifneq ($(filter 1,${STM32MP_EMMC} ${STM32MP_SDMMC}),)
 BL2_SOURCES			+=	drivers/st/mmc/stm32_sdmmc2.c