Limit SPI device debug prints with CONFIG_DEBUG_SPI_FLASH

Fix debug printks which were not using CONFIG_DEBUG_SPI_FLASH,
which would cause long delays durring boot when SPI devices
were written.

Change-Id: I99fc3d5f847fdf4bb98e2a0342ea418ab7d5fc54
Signed-off-by: Marc Jones <marc.jones@se-eng.com>
Reviewed-on: http://review.coreboot.org/1965
Tested-by: build bot (Jenkins)
Reviewed-by: Ronald G. Minnich <rminnich@gmail.com>
diff --git a/src/drivers/spi/spi_flash.c b/src/drivers/spi/spi_flash.c
index 7116cbf..75a5c21 100644
--- a/src/drivers/spi/spi_flash.c
+++ b/src/drivers/spi/spi_flash.c
@@ -162,9 +162,10 @@
 		spi_flash_addr(offset, cmd);
 		offset += erase_size;
 
+#if CONFIG_DEBUG_SPI_FLASH
 		printk(BIOS_SPEW, "SF: erase %2x %2x %2x %2x (%x)\n", cmd[0], cmd[1],
 		      cmd[2], cmd[3], offset);
-
+#endif
 		ret = spi_flash_cmd(flash->spi, CMD_WRITE_ENABLE, NULL, 0);
 		if (ret)
 			goto out;