package/shairport-sync: fix static build issue

Add a patch from upstream to fix static build issue with linking against openssl
and alsa.

Fixes:
http://autobuild.buildroot.net/results/682/6821605cf12e1a5393c29b30baf00cb0f1e1a451/
http://autobuild.buildroot.net/results/3cb/3cb79d566e197771d88e317789d05e9f467f4717/
http://autobuild.buildroot.net/results/9bc/9bcc27461b67e718f49419ba292afd28f1152dc6/
http://autobuild.buildroot.net/results/75a/75afbec6ba4c4b0ae2c18423a0d7eccf098b2eaa/


.. and possibly more.

Signed-off-by: Jörg Krause <joerg.krause@embedded.rocks>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>