clk: imx6q: fix uart earlycon unwork

The earlycon depends on the bootloader setup UART clocks being retained.
There're actually two uart clocks (ipg, per) on MX6QDL,
but the 'Fixes' commit change to register only one which means
another clock may be disabled during booting phase
and result in the earlycon unwork.

Cc: stable@vger.kernel.org # v5.10+
Fixes: 379c9a2 ("clk: imx: Fix reparenting of UARTs not associated with stdout")
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Link: https://lore.kernel.org/r/20210702085438.1988087-1-aisheng.dong@nxp.com
Reviewed-by: Abel Vesa <abel.vesa@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

drivers/clk/imx/clk-imx6q.c

@@ -974,6 +974,6 @@ static void __init imx6q_clocks_init(struct device_node *ccm_node)
 			       hws[IMX6QDL_CLK_PLL3_USB_OTG]->clk);
 	}
 
-	imx_register_uart_clocks(1);
+	imx_register_uart_clocks(2);
 }
 CLK_OF_DECLARE(imx6q, "fsl,imx6q-ccm", imx6q_clocks_init);