configs: stm32mp15: activate DM_REGULATOR_SCMI

Activate the support of SCMI regulator to support the scmi_reg11,
scmi_reg18 and scmi_usb33 regulators present in the scmi device tree of
STMicroelectronics boards with stm32mp15-scmi.dtsi

Fixes: 6cccc8d396bf ("ARM: dts: stm32: add SCMI version of STM32 boards (DK1/DK2/ED1/EV1)")
Signed-off-by: Patrick Delaunay <patrick.delaunay@foss.st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@foss.st.com>
diff --git a/configs/stm32mp15_defconfig b/configs/stm32mp15_defconfig
index fd2a5de..0f6b373 100644
--- a/configs/stm32mp15_defconfig
+++ b/configs/stm32mp15_defconfig
@@ -120,6 +120,7 @@
 CONFIG_DM_REGULATOR_GPIO=y
 CONFIG_DM_REGULATOR_STM32_VREFBUF=y
 CONFIG_DM_REGULATOR_STPMIC1=y
+CONFIG_DM_REGULATOR_SCMI=y
 CONFIG_REMOTEPROC_STM32_COPRO=y
 CONFIG_RESET_SCMI=y
 CONFIG_DM_RNG=y