drivers: spi: fix some typos

Fix some typos in spi drivers

Signed-off-by: Pengfei Fan <fanpengfei1@eswincomputing.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Jagan Teki <jagan@amarulasolutions.com>
diff --git a/drivers/spi/mtk_snfi_spi.c b/drivers/spi/mtk_snfi_spi.c
index 5ea6277..3decb37 100644
--- a/drivers/spi/mtk_snfi_spi.c
+++ b/drivers/spi/mtk_snfi_spi.c
@@ -153,7 +153,7 @@
 
 	/*
 	 * The output data will always be copied to the beginning of
-	 * the GPRAM. Uses word write for better performace.
+	 * the GPRAM. Uses word write for better performance.
 	 *
 	 * Trailing bytes in the last word are not cared.
 	 */
@@ -180,7 +180,7 @@
 
 	/*
 	 * Read aligned data from GPRAM to buffer first.
-	 * Uses word read for better performace.
+	 * Uses word read for better performance.
 	 */
 	i = 0;
 	while (pos < end) {