Join enabled_ssl_apis array

Adds a stdlib join() to the enabled_ssl_apis so we can specify more than one.

Closes bug: #1360978

Change-Id: Ifd290fea802fc926a9e34076393c2c55c3cd9cf5
(cherry picked from commit 816fe4a78a330c2e2c6eb0849566d1777b8e91f6)
Merge "Join enabled_ssl_apis array" into stable/icehouse