ncurses: Fix CVE-2022-29458

ncurses: Fix CVE-2022-29458

ncurses 6.3 before patch 20220416 has an out-of-bounds read and
segmentation violation in convert_strings in tinfo/read_entry.c in the
terminfo library.

Backported from the link below, extracting only the relevant changes.
https://github.com/ThomasDickey/ncurses-snapshots/commit/9d1d651878d4bf0695872a64cc65ba0acb825f36

Signed-off-by: Gustavo Lima Chaves <gustavo.chaves@microsoft.com>
Signed-off-by: Dan Tran <dantran@microsoft.com>
Signed-off-by: Steve Sakoman <steve@sakoman.com>