configs: stm32mp1: replace STM32MP1_TRUSTED by TFABOOT

Activate ARCH_SUPPORT_TFABOOT and replace the arch stm32mp
specific config CONFIG_STM32MP1_TRUSTED by the generic CONFIG_TFABOOT
introduced by the commit 535d76a12150 ("armv8: layerscape: Add TFABOOT
support").
This config CONFIG_TFABOOT is activated for the trusted boot chain,
when U-Boot is loaded by TF-A.

Signed-off-by: Patrick Delaunay <patrick.delaunay@st.com>
Reviewed-by: Patrice Chotard <patrice.chotard@st.com>
diff --git a/include/configs/stm32mp1.h b/include/configs/stm32mp1.h
index 42717c1..2ba4fb1 100644
--- a/include/configs/stm32mp1.h
+++ b/include/configs/stm32mp1.h
@@ -10,7 +10,7 @@
 #include <linux/sizes.h>
 #include <asm/arch/stm32.h>
 
-#ifndef CONFIG_STM32MP1_TRUSTED
+#ifndef CONFIG_TFABOOT
 /* PSCI support */
 #define CONFIG_ARMV7_PSCI_1_0
 #define CONFIG_ARMV7_SECURE_BASE		STM32_SYSRAM_BASE