clk: imx7d: add the missing ipg_root_clk

Add the missing ipg_root_clk which actually is already used by many
orphan clks in current tree.

Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Fabio Estevam <fabio.estevam@nxp.com>
Reviewed-by: Stefan Agner <stefan@agner.ch>
Tested-by: Stefan Agner <stefan@agner.ch>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

drivers/clk/imx/clk-imx7d.c

@@ -386,7 +386,7 @@ static int const clks_init_on[] __initconst = {
 	IMX7D_PLL_SYS_MAIN_480M_CLK, IMX7D_NAND_USDHC_BUS_ROOT_CLK,
 	IMX7D_DRAM_PHYM_ROOT_CLK, IMX7D_DRAM_ROOT_CLK,
 	IMX7D_DRAM_PHYM_ALT_ROOT_CLK, IMX7D_DRAM_ALT_ROOT_CLK,
-	IMX7D_AHB_CHANNEL_ROOT_CLK,
+	IMX7D_AHB_CHANNEL_ROOT_CLK, IMX7D_IPG_ROOT_CLK,
 };
 
 static struct clk_onecell_data clk_data;
@@ -726,6 +726,7 @@ static void __init imx7d_clocks_init(struct device_node *ccm_node)
 	clks[IMX7D_ENET_AXI_ROOT_DIV] = imx_clk_divider2("enet_axi_post_div", "enet_axi_pre_div", base + 0x8900, 0, 6);
 	clks[IMX7D_NAND_USDHC_BUS_ROOT_DIV] = imx_clk_divider2("nand_usdhc_post_div", "nand_usdhc_pre_div", base + 0x8980, 0, 6);
 	clks[IMX7D_AHB_CHANNEL_ROOT_DIV] = imx_clk_divider2("ahb_root_clk", "ahb_pre_div", base + 0x9000, 0, 6);
+	clks[IMX7D_IPG_ROOT_CLK] = imx_clk_divider2("ipg_root_clk", "ahb_root_clk", base + 0x9080, 0, 2);
 	clks[IMX7D_DRAM_ROOT_DIV] = imx_clk_divider2("dram_post_div", "dram_cg", base + 0x9880, 0, 3);
 	clks[IMX7D_DRAM_PHYM_ALT_ROOT_DIV] = imx_clk_divider2("dram_phym_alt_post_div", "dram_phym_alt_pre_div", base + 0xa000, 0, 3);
 	clks[IMX7D_DRAM_ALT_ROOT_DIV] = imx_clk_divider2("dram_alt_post_div", "dram_alt_pre_div", base + 0xa080, 0, 3);