feat(rpi5): add CI build support

Change-Id: I62f0a1025946406eb8c244d0cbc1a8bb40e06c61
Signed-off-by: Mario Bălănică <mariobalanica02@gmail.com>
diff --git a/tf_config/rpi5-default b/tf_config/rpi5-default
new file mode 100644
index 0000000..eecde54
--- /dev/null
+++ b/tf_config/rpi5-default
@@ -0,0 +1,2 @@
+CROSS_COMPILE=aarch64-none-elf-
+PLAT=rpi5