mark libmisc funcs as hidden so they are not exported
add __acl_ prefixes to internal symbols

When static linking libacl, people sometimes run into symbol collisions
because their own code defines symbols like "quote".  So for acl internal
symbols, use an __acl_ prefix.
cp.test: Check permissions of the right file

After "cp -p", the cp.test case was checking the permissions
of the source file instead of the target file.

Reported by: Nic <nic.henke@versity.com>