spi: fsl-(e)spi: Support compile as module

Signed-off-by: Esben Haabendal <eha@deif.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-fsl-lib.h b/drivers/spi/spi-fsl-lib.h
index b4ed04e..1326a39 100644
--- a/drivers/spi/spi-fsl-lib.h
+++ b/drivers/spi/spi-fsl-lib.h
@@ -28,7 +28,7 @@
 	/* rx & tx bufs from the spi_transfer */
 	const void *tx;
 	void *rx;
-#ifdef CONFIG_SPI_FSL_ESPI
+#if IS_ENABLED(CONFIG_SPI_FSL_ESPI)
 	int len;
 #endif
 
@@ -68,7 +68,7 @@
 
 	unsigned int flags;
 
-#ifdef CONFIG_SPI_FSL_SPI
+#if IS_ENABLED(CONFIG_SPI_FSL_SPI)
 	int type;
 	int native_chipselects;
 	u8 max_bits_per_word;