CI: Enable TF-A TFTF test builds

To allow running the TF-A TFTF tests we need to ensure the images for
N1SDP and Corstone-1000 MPS3 boards build

Signed-off-by: Drew Reed <Drew.Reed@arm.com>
Signed-off-by: Jon Mason <jon.mason@arm.com>

ci/tftf.yml

@@ -4,4 +4,5 @@ header:
 local_conf_header:
   tftf: |
     TFA_UBOOT = "0"
+    TFA_UEFI = "0"
     TFTF_TESTS = "1"