staging:rtl8192u: Rename __pTa - Style

The macro parameter __pTa causes a checkpatch issue because of its use
of CamelCase naming. The parameter has this been renamed to addr.

This is a coding style change 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>