Remove empty header annotations in Symbol.map files

[mchoo]

Summary

Commit 42b388439bd3795e09258c57a74ce9eec3651c7b did not completely remove $FreeBSD$ annotation. Leftover empty annotations

/*
 */

Should be removed from Symbol.map files

[mchoo]

Any update?

[olce]

Trivial change that should go in. That said, that may disrupt some changes @imp is doing, so he probably will have the final say as to when this should be merged.

[lwhsu]

This one is done in D42612