mac80211: update linux-firmware

This updates linux-firmware to version 
7f388b4885cf64d6b7833612052d20d4197af96f from 2014-06-04.
In addition it adds new firmware for Intel, Broadcom and Realtek devices.

Signed-off-by: Hauke Mehrtens <hauke@hauke-m.de>


git-svn-id: svn://svn.openwrt.org/openwrt/trunk@41523 3c298f89-4303-0410-b956-a3cf2f4a3e73