commit 86b3bde0 upstream.

The spi command must include the full message length including any
prepended writes, else transfers larger than 256 bytes will be
incomplete.
Signed-off-by: Jonas Gorski <jogo@openwrt.org>
Acked-by: Florian Fainelli <florian@openwrt.org>
Signed-off-by: Mark Brown <broonie@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>