feat(stm32mp2): add fixed regulators support

Call fixed_regulator_register() in bl2_el3_plat_arch_setup() to
configure fixed regulators, if any are present in device tree.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: Iab2d3a4b6b294727b2b6722a6a13bf3f194ec0f9
diff --git a/plat/st/stm32mp2/bl2_plat_setup.c b/plat/st/stm32mp2/bl2_plat_setup.c
index e170609..77b143f 100644
--- a/plat/st/stm32mp2/bl2_plat_setup.c
+++ b/plat/st/stm32mp2/bl2_plat_setup.c
@@ -9,6 +9,7 @@
 
 #include <common/debug.h>
 #include <drivers/clk.h>
+#include <drivers/st/regulator_fixed.h>
 #include <lib/fconf/fconf.h>
 #include <lib/fconf/fconf_dyn_cfg_getter.h>
 #include <lib/mmio.h>
@@ -207,6 +208,10 @@
 	print_reset_reason();
 
 skip_console_init:
+	if (fixed_regulator_register() != 0) {
+		panic();
+	}
+
 	fconf_populate("TB_FW", STM32MP_DTB_BASE);
 
 	stm32mp_io_setup();