staging:rtl8192u: Remove unused enum label CmdID_BBRegWrite10

The enum label CmdID_BBRegWrite10 is not used in the code, so removed from the
source code.

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