* signed/unsigned comparisons
* use standard warn(3)
* Suppress warnings about local vars and funcs not declared static
* const-correctness
* declaration shadows a variable in the global scope
Reviewed by: kevans
MFC after: 2 weeks
Differential Revision: https://reviews.freebsd.org/D26516
and finish the job. ncurses is now the only Makefile in the tree that
uses it since it wasn't a simple mechanical change, and will be
addressed in a future commit.
