Swap order of discovering of -ltinfo and -lterminfo

Summary:
NetBSD ships with native curses(3) and -ltinfo is a part of ncurses.
Set -lterminfo before -ltinfo, as it allows to prioritize native curses
libraries. Mixing curses and ncurses does not work well, especially
in software built on top of llvm.

Original patch by Ryo Onodera (NetBSD) in pkgsrc.

Reviewers: labath, dim, mgorny

Reviewed By: dim, mgorny

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D54650

llvm-svn: 347156