condvar: Disable copy, enable move, and legitimize default ctor
condvar: Disable copy, enable move, and legitimize default ctor

Technically the compiler already did the right things for copy and
move methods because of the spinlock member, but this gives better
error messages if a caller screws up.

aclements/sv6,aclements/sv6,aclements/sv6,aclements/sv6,bowlofstew/sv6,bowlofstew/sv6,bowlofstew/sv6,bowlofstew/sv6,aclements/sv6,bowlofstew/sv6