ncurses: factorize terminfo files installation

This long list of commands to copy the terminfo files from staging to
target is really silly and can be factorized using a
NCURSES_TERMINFO_FILES variable, which is then iterated through.

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
Reviewed-by: Matt Weber <matthew.weber@rockwellcollins.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>