Conditionally apply patch to fix build for 4.12 target

Use boolean parameter LEGACY_SERVER to apply patch.

Change-Id: I079b32215907d02e64ec086a04bbe5d37376a7ef
Signed-off-by: Bernd Hufmann <Bernd.Hufmann@ericsson.com>
diff --git a/jenkins/pipelines/tracecompass-incubator-jdk11.Jenkinsfile b/jenkins/pipelines/tracecompass-incubator-jdk11.Jenkinsfile
index 2c01641..5e8ec6f 100644
--- a/jenkins/pipelines/tracecompass-incubator-jdk11.Jenkinsfile
+++ b/jenkins/pipelines/tracecompass-incubator-jdk11.Jenkinsfile
@@ -66,6 +66,16 @@
                 }
             }
         }
+        stage('Legacy-server') {
+            when {
+                expression { return params.LEGACY_SERVER }
+            }
+            steps {
+                container('tracecompass') {
+                    sh 'git am patches/0001-releng-Fix-build-with-tracecompass-incubator-2019-06.patch'
+                }
+            }
+        }
         stage('Build') {
             steps {
                 container('tracecompass') {
diff --git a/jenkins/pipelines/tracecompass-incubator.Jenkinsfile b/jenkins/pipelines/tracecompass-incubator.Jenkinsfile
index d41b125..41497da 100644
--- a/jenkins/pipelines/tracecompass-incubator.Jenkinsfile
+++ b/jenkins/pipelines/tracecompass-incubator.Jenkinsfile
@@ -66,6 +66,16 @@
                 }
             }
         }
+        stage('Legacy-server') {
+            when {
+                expression { return params.LEGACY_SERVER }
+            }
+            steps {
+                container('tracecompass') {
+                    sh 'git am patches/0001-releng-Fix-build-with-tracecompass-incubator-2019-06.patch'
+                }
+            }
+        }
         stage('Build') {
             steps {
                 container('tracecompass') {