clk: clk-fixed-mmio: Demote obvious kernel-doc abuse

Fixes the following W=1 kernel build warning(s):

 drivers/clk/clk-fixed-mmio.c:62: warning: Function parameter or member 'pdev' not described in 'of_fixed_mmio_clk_probe'

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Jan Kotas <jank@cadence.com>
Cc: linux-clk@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210126124540.3320214-15-lee.jones@linaro.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/clk-fixed-mmio.c

@@ -55,7 +55,7 @@ static void __init of_fixed_mmio_clk_setup(struct device_node *node)
 }
 CLK_OF_DECLARE(fixed_mmio_clk, "fixed-mmio-clock", of_fixed_mmio_clk_setup);
 
-/**
+/*
  * This is not executed when of_fixed_mmio_clk_setup succeeded.
  */
 static int of_fixed_mmio_clk_probe(struct platform_device *pdev)