ByteBuffer::align() does not work as expected
on some RTEMS targets where malloc() returns
buffers aligned only to 4 bytes.
SerializableControl::alignBuffer() and
DeserializableControl::alignData() are implemented,
but never called, in this module and pvAccessCPP.
ByteBuffer::align() is only needed to implement
these two methods.
Leave non-pure virtual stubs to assist in migration.
07b79693af