build(stm32mp1): add scripts for STM32MP13

Add the required files to compile STM32MP13 variant of STM32MP1.

Signed-off-by: Yann Gautier <yann.gautier@st.com>
Change-Id: I5078f6c29d962c1c7090458fd6438380587ee786
diff --git a/tf_config/stm32mp1-mp13 b/tf_config/stm32mp1-mp13
new file mode 100644
index 0000000..489e9a0
--- /dev/null
+++ b/tf_config/stm32mp1-mp13
@@ -0,0 +1,9 @@
+AARCH32_SP=optee
+ARCH=aarch32
+ARM_ARCH_MAJOR=7
+CROSS_COMPILE=arm-none-eabi-
+PLAT=stm32mp1
+STM32MP13=1
+STM32MP_EMMC=1
+STM32MP_SDMMC=1
+DTB_FILE_NAME=stm32mp135f-dk.dtb