[PATCH] pwm: stm32: fix build warning with CONFIG_DMA_ENGINE disabled

[Arnd Bergmann]

Without dmaengine support, we get a harmless warning about an
unused function:

drivers/pwm/pwm-stm32.c:166:12: error: 'stm32_pwm_capture' defined but not used [-Werror=unused-function]

Changing the #ifdef to an IS_ENABLED() check shuts up that warning
and is slightly nicer to read.

Fixes: 53e38fe73f94 ("pwm: stm32: Add capture support")
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
 drivers/pwm/pwm-stm32.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/pwm/pwm-stm32.c b/drivers/pwm/pwm-stm32.c
index 60bfc07c4912..97bbc1f18fd6 100644
--- a/drivers/pwm/pwm-stm32.c
+++ b/drivers/pwm/pwm-stm32.c
@@ -484,9 +484,7 @@ static int stm32_pwm_apply_locked(struct pwm_chip *chip, struct pwm_device *pwm,
 static const struct pwm_ops stm32pwm_ops = {
 	.owner = THIS_MODULE,
 	.apply = stm32_pwm_apply_locked,
-#if IS_ENABLED(CONFIG_DMA_ENGINE)
-	.capture = stm32_pwm_capture,
-#endif
+	.capture = IS_ENABLED(CONFIG_DMA_ENGINE) ? stm32_pwm_capture : NULL,
 };
 
 static int stm32_pwm_set_breakinput(struct stm32_pwm *priv,
-- 
2.9.0