Add CFE support to the BCM47XX code.  That includes querying CFE environment
variables as well as using CFE to print messages before the serial port is
initialized (early printk).
Signed-off-by: NAurelien Jarno <aurel32@farad.aurel32.net>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>

Note that the BCM4710 does not support the wait instruction, this
is not a mistake in the code.
    
It originally comes from the OpenWrt patches.
    
Cc: Michael Buesch <mb@bu3sch.de>
Cc: Felix Fietkau <nbd@openwrt.org>
Cc: Florian Schirmer <jolt@tuxbox.org>
Signed-off-by: NAurelien Jarno <aurelien@aurel32.net>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NRalf Baechle <ralf@linux-mips.org>