Do not override managed tycho-version.

Change-Id: I0095ee479fca201311499cc82c18b749b1c1fad9
Signed-off-by: Alexander Kurtakov <akurtako@redhat.com>

pom.xml

diff --git a/pom.xml b/pom.xml
index fc93139..184ffa3 100644
--- a/pom.xml
+++ b/pom.xml
@@ -77,7 +77,6 @@
 			<plugin>
 				<groupId>org.eclipse.tycho</groupId>
 				<artifactId>tycho-packaging-plugin</artifactId>
-				<version>${tycho.version}</version>
 				<configuration>
 					<sourceReferences>
 						<generate>true</generate>