clk: imx7d: correct dram root clk parent select

DRAM root clk should be either from pll dram main clk
or dram alt root clk.
Signed-off-by: Anson Huang <b20788@freescale.com>
Signed-off-by: Dong Aisheng <aisheng.dong@nxp.com>
Signed-off-by: Shawn Guo <shawnguo@kernel.org>

drivers/clk/imx/clk-imx7d.c

@@ -65,7 +65,7 @@ static const char *dram_phym_sel[] = { "pll_dram_main_clk",
 	"dram_phym_alt_clk", };
 
 static const char *dram_sel[] = { "pll_dram_main_clk",
-	"dram_alt_clk", };
+	"dram_alt_root_clk", };
 
 static const char *dram_phym_alt_sel[] = { "osc", "pll_dram_533m_clk",
 	"pll_sys_main_clk", "pll_enet_500m_clk",