clk: bcm: rpi: Rename is_prepared function

The raspberrypi_fw_pll_is_on function doesn't only apply to PLL
registered in the driver, but any clock exposed by the firmware.

Since we also implement the is_prepared hook, make the function
consistent with the other function names.

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: linux-clk@vger.kernel.org
Acked-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Tested-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
Link: https://lore.kernel.org/r/ac93cc4e245316bb7e7426ac5ab0de8f3d919731.1592210452.git-series.maxime@cerno.techSigned-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/bcm/clk-raspberrypi.c

@@ -85,7 +85,7 @@ static int raspberrypi_clock_property(struct rpi_firmware *firmware,
 	return 0;
 }
 
-static int raspberrypi_fw_pll_is_on(struct clk_hw *hw)
+static int raspberrypi_fw_is_prepared(struct clk_hw *hw)
 {
 	struct raspberrypi_clk_data *data =
 		container_of(hw, struct raspberrypi_clk_data, hw);
@@ -166,7 +166,7 @@ static int raspberrypi_pll_determine_rate(struct clk_hw *hw,
 }
 
 static const struct clk_ops raspberrypi_firmware_pll_clk_ops = {
-	.is_prepared = raspberrypi_fw_pll_is_on,
+	.is_prepared = raspberrypi_fw_is_prepared,
 	.recalc_rate = raspberrypi_fw_pll_get_rate,
 	.set_rate = raspberrypi_fw_pll_set_rate,
 	.determine_rate = raspberrypi_pll_determine_rate,