staging:rtl8192u: rename OCTET_STRING - Style

Rename the structure OCTET_STRING to octet_string. This is to comply
with the coding style of using lowercase for types. In addition the
typedef directive is removed to clear the checkpatch issue with
defining new types.

These are coding style changes which should have no impact on runtime
code execution.

Signed-off-by: John Whitmore <johnfwhitmore@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>