clk: bcm: clk-iproc-pll: Demote kernel-doc abuse

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

 drivers/clk/bcm/clk-iproc-pll.c:712: warning: Function parameter or member 'pll' not described in 'iproc_pll_sw_cfg'

Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Ray Jui <rjui@broadcom.com>
Cc: Scott Branden <sbranden@broadcom.com>
Cc: bcm-kernel-feedback-list@broadcom.com
Cc: linux-clk@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210120093040.1719407-6-lee.jones@linaro.org


Signed-off-by: Stephen Boyd <sboyd@kernel.org>