spi: add support for Amlogic A1 SPI Flash Controller

Add A1 SPIFC driver from Linux. Slightly modified to use u-boot driver
framework and accommodate to lack of ioread32_rep/iowrite32_rep.

Based on Linux version 6.6-rc4

Signed-off-by: Igor Prusov <IVPrusov@sberdevices.ru>
Signed-off-by: Martin Kurbanov <mmkurbanov@sberdevices.ru>
Reviewed-by: Simon Glass <sjg@chromium.org>
Link: https://lore.kernel.org/r/20231024225140.366571-2-ivprusov@sberdevices.ru


Signed-off-by: Neil Armstrong <neil.armstrong@linaro.org>
[trini: Drop <common.h> as it's not needed]