thermal/drivers/broadcom: Use clamp to simplify bcm2835_thermal_temp2adc

Use clamp() to simplify bcm2835_thermal_temp2adc() and improve its
readability. Explicitly cast BIT() to int to prevent a signedness error.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com>
Link: https://patch.msgid.link/20260105121308.1761-1-thorsten.blum@linux.dev
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

Author: toblux

drivers/thermal/broadcom/bcm2835_thermal.c

@@ -11,6 +11,7 @@
 #include <linux/err.h>
 #include <linux/io.h>
 #include <linux/kernel.h>
+#include <linux/minmax.h>
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/of_address.h>
@@ -80,12 +81,7 @@ static int bcm2835_thermal_temp2adc(int temp, int offset, int slope)
 	temp -= offset;
 	temp /= slope;
 
-	if (temp < 0)
-		temp = 0;
-	if (temp >= BIT(BCM2835_TS_TSENSSTAT_DATA_BITS))
-		temp = BIT(BCM2835_TS_TSENSSTAT_DATA_BITS) - 1;
-
-	return temp;
+	return clamp(temp, 0, (int)BIT(BCM2835_TS_TSENSSTAT_DATA_BITS) - 1);
 }
 
 static int bcm2835_thermal_get_temp(struct thermal_zone_device *tz, int *temp)