package/libwebsock: allow building without SSL

libwebsock can optionally use SL, and defaults to using it without
checking for its presence first.

Just disable SSL support if openssl is not enabled, and ensure it is
built before libwebsock if it is enabled.

Add a patch to fix SSL conditional build.

Fixes:
    http://autobuild.buildroot.org/results/2c4/2c49e45667aaf2f2a59ace94885b9d4ed98038d7/
    http://autobuild.buildroot.org/results/517/517bc814732f86dc6dd1a5c91148ce52ec9803f7/
    http://autobuild.buildroot.org/results/951/95109c7e37aa21228bc71c69e9c66a6821f3174a/


    ...

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Cc: Gregory Dymarek <gregd72002@gmail.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>