Fix assembly xmls for maven-assembly-plugin v2.2+

Fix assembly xmls for maven-assembly-plugin v2.2+

Starting in version 2.2, maven-assembly-plugin
requires an id tag in the assembly descriptor xmls.
This patch allows the project to be built in
environments that use newer versions of
maven-assembly-plugin.

For details, see:
https://issues.apache.org/jira/browse/MASSEMBLY-517

Change-Id: I3a721da4aa47be58127fa3f8971f01635d400185
Signed-off-by: Gary Wu <gary.i.wu@huawei.com>