ci(msm8916): add build config for new platforms

Add build configs for the new mdm9607, msm8909 and msm8939 platforms
which are very similar to the existing msm8916 but build the code in
different configurations.

mdm9607 and msm8909 are AArch32-only so they can only use SP_MIN.

Change-Id: I8bb9cce3bb0bd3df7576c3e8b2ea00ed460aff2e
Signed-off-by: Stephan Gerhold <stephan@gerhold.net>
diff --git a/tf_config/msm8909-default b/tf_config/msm8909-default
new file mode 100644
index 0000000..22d518c
--- /dev/null
+++ b/tf_config/msm8909-default
@@ -0,0 +1,4 @@
+AARCH32_SP=sp_min
+ARCH=aarch32
+CROSS_COMPILE=arm-none-eabi-
+PLAT=msm8909