clk: renesas: Fix incorrect return RPC clk_get_rate

RPC clk_get_rate will return error code instead of expected clock rate.
Fix this.

Signed-off-by: Hai Pham <hai.pham.ud@renesas.com>
Signed-off-by: Marek Vasut <marek.vasut+renesas@gmail.com>
1 file changed