net:wimax: Fix doucble word "the the" in networking.xml

This patch fix a double word "the the"
in Documentation/DocBook/networking.xml and
Documentation/DocBook/networking/API-Wimax-report-rfkill-sw.html.

These files are generated from comment in source, so I had to
fix the typo in net/wimax/io-rfkill.c

Signed-off-by: Masanari Iida <standby24x7@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>