spi: fsi: Make available for build test

There is no build time dependency on the platform support so add an
|| COMPILE_TEST so we've got better build coverage of the driver.
Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20230221-spi-arch-deps-v1-5-83d1566474cf@kernel.orgSigned-off-by: Mark Brown <broonie@kernel.org>

drivers/spi/Kconfig

@@ -357,7 +357,7 @@ config SPI_FALCON
 
 config SPI_FSI
 	tristate "FSI SPI driver"
-	depends on FSI
+	depends on FSI || COMPILE_TEST
 	help
 	  This enables support for the driver for FSI bus attached SPI
 	  controllers.