lvm: remove duplicate call to lvm_submit()

This got added by accident when solving the merge conflict in 103f05e0.

It led to the plugin triggering the classical "uc_update: Value too old"
error message.
Merge pull request #791 from mfournier/fix-lvm-merge-conflict-mistake

lvm: remove duplicate call to lvm_submit()
Merge branch 'master' into debian
updating build.sh results
Merge branch "debian" into debian-wheezy-backports