b43: drop Copyright for not really copyrightable info

As discussed in "Licensing wlc_phy_radio.h and brcm80211" (Message-ID:
<AANLkTinQMRGkOvi4e4JMsHGV_BF_4Rf5oHCtZgQjwQ1g@mail.gmail.com>) content
of that file is not copyrightable, just names and numbers.

Signed-off-by: Rafał Miłecki <zajec5@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>