clk: scpi: fix return type of __scpi_dvfs_round_rate

The frequencies above the maximum value of signed integer(i.e. 2^31 -1)
will overflow with the current code.

This patch fixes the return type of __scpi_dvfs_round_rate from 'int'
to 'unsigned long'.

Fixes: cd52c2a4 ("clk: add support for clocks provided by SCP(System Control Processor)")
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/clk-scpi.c

@@ -71,15 +71,15 @@ static const struct clk_ops scpi_clk_ops = {
 };
 
 /* find closest match to given frequency in OPP table */
-static int __scpi_dvfs_round_rate(struct scpi_clk *clk, unsigned long rate)
+static long __scpi_dvfs_round_rate(struct scpi_clk *clk, unsigned long rate)
 {
 	int idx;
-	u32 fmin = 0, fmax = ~0, ftmp;
+	unsigned long fmin = 0, fmax = ~0, ftmp;
 	const struct scpi_opp *opp = clk->info->opps;
 
 	for (idx = 0; idx < clk->info->count; idx++, opp++) {
 		ftmp = opp->freq;
-		if (ftmp >= (u32)rate) {
+		if (ftmp >= rate) {
 			if (ftmp <= fmax)
 				fmax = ftmp;
 			break;