uboot-imx

ppc4xx: Complete remove bogus dflush()

Since the current dflush() implementation is know to have some problems
(as seem on lwmon5 ECC init) this patch removes it completely and replaces
it by using clean_dcache_range().

Tested on Katmai with ECC DIMM.

Signed-off-by: Stefan Roese <sr@denx.de>