gstreamer-plugins-bad: replace openssl dependency with nettle for hls plugin

gstreamer-plugins-bad: replace openssl dependency with nettle for hls plugin

It has not been ported to openssl 1.1 (and there's nothing in upstream git),
but it's possible to use nettle or gcrypt intead.

Also, provide a fallback option to use openssl 1.0 when necessary.

(From OE-Core rev: 624aed5d450664b0f0a36b14d658248202f864ed)

Signed-off-by: Alexander Kanavin <alexander.kanavin@linux.intel.com>
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>