The first of these two patches is by Stefano Brivio and removes extra MMIO
references in the interrupt routine. I am submitting it on Stefano's behalf
because I was able to test it, and his patch touches the routine that patch 2 fixes.
The second patch fixes a locking problem introduced by commit
abb1d2bca0fc429c136747a64e675dd4d8906f36 "mac80211: unify config_interface and
bss_info_changed". After that patch was applied, b43legacy would lock the system
upon booting.