staging: brcm80211: removed softmac files alloc.c/alloc.h

Alloc.c does not contain enough functionality anymore to warrant
its own file. Moved functionality into main.c

Reported-by: Johannes Berg <johannes@sipsolutions.net>
Reviewed-by: Arend van Spriel <arend@broadcom.com>
Signed-off-by: Roland Vossen <rvossen@broadcom.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>