Add build config for imx8mp platform

Change-Id: Ife4b74712f43d406e2bbbafd100693158d13f095
Signed-off-by: Madhukar Pappireddy <madhukar.pappireddy@arm.com>
Signed-off-by: Sandrine Bailleux <sandrine.bailleux@arm.com>
diff --git a/tf_config/imx8mp-default b/tf_config/imx8mp-default
new file mode 100644
index 0000000..38ddc12
--- /dev/null
+++ b/tf_config/imx8mp-default
@@ -0,0 +1,2 @@
+CROSS_COMPILE=aarch64-none-elf-
+PLAT=imx8mp