Input: misc - use __maybe_unused instead of ifdef around suspend/resume

Use __maybe_unused instead of ifdef guards around suspend/resume
functions, in order to increase build coverage and fix build warnings.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
diff --git a/drivers/input/misc/ad714x-spi.c b/drivers/input/misc/ad714x-spi.c
index 3a90b710..a79e50b 100644
--- a/drivers/input/misc/ad714x-spi.c
+++ b/drivers/input/misc/ad714x-spi.c
@@ -16,17 +16,15 @@
 #define AD714x_SPI_CMD_PREFIX      0xE000   /* bits 15:11 */
 #define AD714x_SPI_READ            BIT(10)
 
-#ifdef CONFIG_PM_SLEEP
-static int ad714x_spi_suspend(struct device *dev)
+static int __maybe_unused ad714x_spi_suspend(struct device *dev)
 {
 	return ad714x_disable(spi_get_drvdata(to_spi_device(dev)));
 }
 
-static int ad714x_spi_resume(struct device *dev)
+static int __maybe_unused ad714x_spi_resume(struct device *dev)
 {
 	return ad714x_enable(spi_get_drvdata(to_spi_device(dev)));
 }
-#endif
 
 static SIMPLE_DEV_PM_OPS(ad714x_spi_pm, ad714x_spi_suspend, ad714x_spi_resume);