clk: bcm2835: fix bcm2835_clock_rate_from_divisor declaration

The return value of bcm2835_clock_rate_from_divisor is always unsigned
and also all caller expect this. So fix the declaration accordingly.

Fixes: 41691b8 ("clk: bcm2835: Add support for programming the audio domain clocks")
Signed-off-by: Stefan Wahren <stefan.wahren@i2se.com>
Link: https://lore.kernel.org/r/20220904141037.38816-1-stefan.wahren@i2se.com
Reviewed-by: Ivan T. Ivanov <iivanov@suse.de>
Reviewed-by: Florian Fainelli <f.fainelli@gmail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

Author: Stefan Wahren

drivers/clk/bcm/clk-bcm2835.c

@@ -969,9 +969,9 @@ static u32 bcm2835_clock_choose_div(struct clk_hw *hw,
 	return div;
 }
 
-static long bcm2835_clock_rate_from_divisor(struct bcm2835_clock *clock,
-					    unsigned long parent_rate,
-					    u32 div)
+static unsigned long bcm2835_clock_rate_from_divisor(struct bcm2835_clock *clock,
+						     unsigned long parent_rate,
+						     u32 div)
 {
 	const struct bcm2835_clock_data *data = clock->data;
 	u64 temp;