Short version: svn add * –force is all you need
Long version:
According to svn add manual page
Normally, the command svn add * will skip over any directories that are already under version control. Sometimes, however, you may want to add every unversioned object in your working copy, including those hiding deeper down. Passing the –force option makes svn add recurse into versioned directories:
$ svn add * --force
A foo.c
A somedir/bar.c
A otherdir/docs/baz.doc