staging: wlan-ng: prism2mgmt.c Fix break not useful

Fixed up warnings, break is not useful after return statement.
And the exit Label is deleted, now returning inline.

Signed-off-by: Jeshwanth Kumar N K <jeshkumar555@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>