change dock_function_info to a class

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10074 387891d4-d844-0410-90c0-e4c51a9137d3
change p_dock_function_info to a class as well

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10075 387891d4-d844-0410-90c0-e4c51a9137d3
ugh, neither the constructor nor the memsets are actually needed here

git-svn-id: svn://svn.icculus.org/fs2open/trunk/fs2_open@10076 387891d4-d844-0410-90c0-e4c51a9137d3