clk: socfpga: remove redundant assignment on division

The variable parent_rate is being divided by div and the result
is re-assigned to parent_rate before being returned. The assignment
is redundant, replace /= operator with just / operator.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Link: https://lore.kernel.org/r/20211221003750.212780-1-colin.i.king@gmail.comAcked-by: Dinh Nguyen <dinguyen@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/socfpga/clk-pll-s10.c

@@ -113,7 +113,7 @@ static unsigned long clk_boot_clk_recalc_rate(struct clk_hw *hwclk,
 		SWCTRLBTCLKSEL_MASK) >>
 		SWCTRLBTCLKSEL_SHIFT);
 	div += 1;
-	return parent_rate /= div;
+	return parent_rate / div;
 }