feat(st): add USB and UART build config

Add build configurations for USB and UART use-cases. Those are used
when programming the boot device.
Those missing configurations were highlighted with compilation issues:
https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/16973

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: I223496c9c3dfe51f203d7e51f83c565fbd13f9a4
diff --git a/group/tf-l1-build-plat/stm32mp1-uart:nil b/group/tf-l1-build-plat/stm32mp1-uart:nil
new file mode 100644
index 0000000..0849ee7
--- /dev/null
+++ b/group/tf-l1-build-plat/stm32mp1-uart:nil
@@ -0,0 +1,6 @@
+#
+# Copyright (c) 2022 Arm Limited. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
diff --git a/group/tf-l1-build-plat/stm32mp1-usb:nil b/group/tf-l1-build-plat/stm32mp1-usb:nil
new file mode 100644
index 0000000..0849ee7
--- /dev/null
+++ b/group/tf-l1-build-plat/stm32mp1-usb:nil
@@ -0,0 +1,6 @@
+#
+# Copyright (c) 2022 Arm Limited. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
diff --git a/tf_config/stm32mp1-uart b/tf_config/stm32mp1-uart
new file mode 100644
index 0000000..f4afdf2
--- /dev/null
+++ b/tf_config/stm32mp1-uart
@@ -0,0 +1,7 @@
+AARCH32_SP=sp_min
+ARCH=aarch32
+ARM_ARCH_MAJOR=7
+CROSS_COMPILE=arm-none-eabi-
+DTB_FILE_NAME=stm32mp157c-ev1.dtb
+PLAT=stm32mp1
+STM32MP_UART_PROGRAMMER=1
diff --git a/tf_config/stm32mp1-usb b/tf_config/stm32mp1-usb
new file mode 100644
index 0000000..ed6945b
--- /dev/null
+++ b/tf_config/stm32mp1-usb
@@ -0,0 +1,7 @@
+AARCH32_SP=sp_min
+ARCH=aarch32
+ARM_ARCH_MAJOR=7
+CROSS_COMPILE=arm-none-eabi-
+DTB_FILE_NAME=stm32mp157c-ev1.dtb
+PLAT=stm32mp1
+STM32MP_USB_PROGRAMMER=1