ARM: 6859/1: Add writethrough dcache support for ARM926EJS processor
The ARM kernel supports writethrough data cache via the
CONFIG_CPU_DCACHE_WRITETHROUGH option. However, that
functionality wasn't implemented in the arch/arm/boot/compressed
code. It is now necessary due to a new ARM926EJS processor
that has an issue with writeback data cache.
Signed-off-by: Mark A. Greer <mgreer@mvista.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>