clk: bcm: Fix 'maybe-uninitialized' warning in bcm2835_clock_choose_div_and_prate()

best_rate is reported as potentially uninitialized by gcc.
Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Fixes: 155e8b3b ("clk: bcm: Support rate change propagation on bcm2835 clocks")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reviewed-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/bcm/clk-bcm2835.c

@@ -1029,7 +1029,7 @@ static unsigned long bcm2835_clock_choose_div_and_prate(struct clk_hw *hw,
 	struct bcm2835_clock *clock = bcm2835_clock_from_hw(hw);
 	struct bcm2835_cprman *cprman = clock->cprman;
 	const struct bcm2835_clock_data *data = clock->data;
-	unsigned long best_rate;
+	unsigned long best_rate = 0;
 	u32 curdiv, mindiv, maxdiv;
 	struct clk_hw *parent;