Remove symlink src/libmtcp.a.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2596 ba6dc0ae-232f-0410-883f-9ebac64fc565
MTCP: Remove libmtcp.a with make clean.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2597 ba6dc0ae-232f-0410-883f-9ebac64fc565
Toplevel distclean fix.

git-svn-id: svn://svn.code.sf.net/p/dmtcp/code/trunk@2598 ba6dc0ae-232f-0410-883f-9ebac64fc565