soc/intel/common/block/fast_spi: don't include all spi flash drivers

The fast spi driver implements hardware sequencing which abstracts away
the underlying spi flash commands in the hardware block. It also has its
own spi flash probe function to intercept the spi flash ops. As such it's
not necessary to include all spi flash drivers.

On a hatch Chrome OS build this saves 9.5KiB of text in each of verstage,
romstage, and ramstage.

Change-Id: Ifb1b962cde3a6a02353ddf83279234057a9ec2fa
Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/38363
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>

src/soc/intel/skylake/Kconfig

@@ -77,7 +77,6 @@ config CPU_SPECIFIC_OPTIONS
 	select TSC_SYNC_MFENCE
 	select UDELAY_TSC
 	select UDK_2015_BINDING
-	select SPI_FLASH_DONT_INCLUDE_ALL_DRIVERS
 
 config FSP_HYPERTHREADING
 	bool "Enable Hyper-Threading"