[PATCH] staging: pi433: pi433_if.c Fix SET_CHECKED style issues

[Nguyen Phan Quang Minh]

Fix checkpatch warning and add result holder variable to reduce overhead
since the macro is called on functions.

Signed-off-by: Nguyen Phan Quang Minh <minhnpq16@xxxxxxxxx>
---
Since SET_CHECKED has a return statement, I'm very tempted to straight
up remove it and do the checking inline. But the macro is used a lot
(~60 times), I think it might hurt the readability of the code.

 drivers/staging/pi433/pi433_if.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/drivers/staging/pi433/pi433_if.c b/drivers/staging/pi433/pi433_if.c
index 3404cb9722c9..77ab2986b985 100644
--- a/drivers/staging/pi433/pi433_if.c
+++ b/drivers/staging/pi433/pi433_if.c
@@ -122,9 +122,12 @@ struct pi433_instance {
 /*-------------------------------------------------------------------------*/
 
 /* macro for checked access of registers of radio module */
-#define SET_CHECKED(retval) \
-	if (retval < 0) \
-		return retval;
+#define SET_CHECKED(func)		\
+	do {				\
+		int retval = func;	\
+		if (retval < 0)		\
+			return retval;	\
+	} while (0)
 
 /*-------------------------------------------------------------------------*/
 
-- 
2.15.1