texinfo: update to 6.7

Drop 0001-Unset-need_charset_alias-when-building-for-musl.patch
as the problematic code is gone.

Rebase the other patches.

License-Update: http links changed to https
Signed-off-by: Alexander Kanavin <alex.kanavin@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>