clk: ti: clkt_dpll: Fix some kernel-doc misdemeanours

clk: ti: clkt_dpll: Fix some kernel-doc misdemeanours

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

 drivers/clk/ti/clkt_dpll.c:284: warning: Function parameter or member 'hw' not described in 'omap2_dpll_round_rate'
 drivers/clk/ti/clkt_dpll.c:284: warning: Function parameter or member 'parent_rate' not described in 'omap2_dpll_round_rate'
 drivers/clk/ti/clkt_dpll.c:284: warning: Excess function parameter 'clk' description in 'omap2_dpll_round_rate'

Cc: Tero Kristo <kristo@kernel.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: Richard Woodruff <r-woodruff2@ti.com>
Cc: linux-omap@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Link: https://lore.kernel.org/r/20210126124540.3320214-3-lee.jones@linaro.org
Reviewed-by: Tero Kristo <kristo@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>