build-sys: use tinfo *or* ncurses for more(1), ul(1) and setterm(1)

 * it seems that we don't have to link the utils with ncurses, tinfo is enough.
   This change saves one unnecessary dependence.

 * libtinfo is also distributed with pkg-config files, so we can use
   PKG_CHECK_MODULES() as a primary source for LIBS and CFLAGS.

 * add TINFO_CFLAGS (although it's probably always empty)

Signed-off-by: Karel Zak <kzak@redhat.com>