nicintel_spi.c: Implement `set_sck_set_mosi` and `set_sck_get_miso`

Tested on a 8086:1533 (i210 GbE), reads still return the same data.
This cuts the time to read a Winbond W25Q80.V (1 MiB, SPI) from 66
seconds down to 48 seconds, i.e. a 37.5% increase in speed.

flashrom-stable: backported to use globals

Change-Id: I52a0ae5ff331ee2ed41652eb5c2ed7ebe7253d74
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Original-Reviewed-on: https://review.coreboot.org/c/flashrom/+/49267
Original-Reviewed-by: Nico Huber <nico.h@gmx.de>
Reviewed-on: https://review.coreboot.org/c/flashrom-stable/+/71428
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
1 file changed