clk: imx: fix composite peripheral flags

According to RM, for peripheral clock slice,
"IP clock slices must be stopped to change the clock source.".

So we must have CLK_SET_PARENT_GATE flag to avoid glitch.
Signed-off-by: Peng Fan <peng.fan@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

drivers/clk/imx/clk-composite-8m.c

@@ -216,6 +216,7 @@ struct clk_hw *imx8m_clk_hw_composite_flags(const char *name,
 		div->width = PCG_PREDIV_WIDTH;
 		divider_ops = &imx8m_clk_composite_divider_ops;
 		mux_ops = &clk_mux_ops;
+		flags |= CLK_SET_PARENT_GATE;
 	}
 
 	div->lock = &imx_ccm_lock;