Sync tf_config files with internal CI

Signed-off-by: Zelalem <zelalem.aweke@arm.com>
Change-Id: I064f4f252fe7d3770719dee040feb96ea180a9bb
diff --git a/tf_config/stingray-default b/tf_config/stingray-default
new file mode 100644
index 0000000..31bb3a2
--- /dev/null
+++ b/tf_config/stingray-default
@@ -0,0 +1,3 @@
+CROSS_COMPILE=aarch64-none-elf-
+BOARD_CFG=bcm958742t
+PLAT=stingray