Revert "lava-templates: Comment out "license_variable" param"

This reverts commit 1293a1412661fb1d48a0fe444efaa8860db6f9e6.

Reason for revert: TF-A CI uses non-UBL-enabled FVP models which
are hard to upgrade. All relevant parties were notified and aware
of the issue, but work on that may conflict with the preparation
of the upcoming release. We are starting with the contingency plan
of still extending FlexNet licenses expiration. The matter to be
revisited in June 2024

More info in https://linaro.atlassian.net/browse/TFC-608

Change-Id: I3d092e7558dc84dc2683ac30258a32b258896b0c
diff --git a/script/lava-templates/fvp-linux.yaml b/script/lava-templates/fvp-linux.yaml
index e6969fe..597354b 100644
--- a/script/lava-templates/fvp-linux.yaml
+++ b/script/lava-templates/fvp-linux.yaml
@@ -60,7 +60,7 @@
 
 - boot:
     method: fvp
-#    license_variable: ARMLMD_LICENSE_FILE=${armlmd_license_file}
+    license_variable: ARMLMD_LICENSE_FILE=${armlmd_license_file}
     docker:
       name: ${docker_name}
       local: true
diff --git a/script/lava-templates/fvp-tftf.yaml b/script/lava-templates/fvp-tftf.yaml
index 2d81baa..82287f6 100644
--- a/script/lava-templates/fvp-tftf.yaml
+++ b/script/lava-templates/fvp-tftf.yaml
@@ -73,7 +73,7 @@
 
 - boot:
     method: fvp
-#    license_variable: ARMLMD_LICENSE_FILE=${armlmd_license_file}
+    license_variable: ARMLMD_LICENSE_FILE=${armlmd_license_file}
     docker:
       name: ${docker_name}
       local: true