emulators/virtualbox-ose: Fix build with ports provided SSL library on 11.x

Due to a compiler/linker command line ordering issue, VirtualBox 6
fails to compile on 11.x when a ports provided SSL library is
used.

Fix the order of -L options passed to the linker where the ssl
library is used.

Thanks to Chad Jacob Milios <milios@ccsys.com> for suggesting the
correct fix.

PR: 254295
Submitted by: russo@bogodyn.org
MFH: 2021Q2

(cherry picked from commit 423f3dfd755f7c98bf2d28083aac19783cf4e9a6)