spi/atmel: fix speed_hz check in atmel_spi_transfer()
atmel_spi_transfer() would check speed_hz and fail if
the speed was changed in the transfer. After commit
"spi: make sure all transfer has proper speed set"
this would happen on all transfers.
Change speed_hz check to only fail if a lower speed
than max is requested.
Signed-off-by: Joachim Eastwood <manabian@gmail.com> Acked-by: Nicolas Ferre <nicolas.ferre@atmel.com> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>