clk: fix clk_get_rate() always return ulong

When we call clk_get_rate(), we expect to get clock rate value as
ulong.
In that case we should not use log_ret() macro since it use internally
an int.
Otherwise we may return an invalid/truncated clock rate value.

Signed-off-by: Julien Masson <jmasson@baylibre.com>
Fixes: 5c5992cb ("clk: Add debugging for return values")
Reviewed-by: Sean Anderson <seanga2@gmail.com>
Reviewed-by: Mattijs Korpershoek <mkorpershoek@baylibre.com>
Link: https://lore.kernel.org/r/87o7erv9p4.fsf@baylibre.com