clk: ti: dra7: fix "failed to lookup clock node gmac_gmii_ref_clk_div" boot message

Prevent creating clk alias for non existing gmac_gmii_ref_clk_div clock and,
this way, eliminate excessive error message during boot:

"ti_dt_clocks_register: failed to lookup clock node gmac_gmii_ref_clk_div"

Fixes: c097338ebd3f ("ARM: dts: dra7: cpsw: fix clocks tree")
Signed-off-by: Grygorii Strashko <[e-mail]>
Signed-off-by: Stephen Boyd <[e-mail]>

drivers/clk/ti/clk-7xx.c

···
 	DT_CLK(NULL, "atl_dpll_clk_mux", "atl_dpll_clk_mux"),
 	DT_CLK(NULL, "atl_gfclk_mux", "atl_gfclk_mux"),
 	DT_CLK(NULL, "dcan1_sys_clk_mux", "dcan1_sys_clk_mux"),
-	DT_CLK(NULL, "gmac_gmii_ref_clk_div", "gmac_gmii_ref_clk_div"),
 	DT_CLK(NULL, "gmac_rft_clk_mux", "gmac_rft_clk_mux"),
 	DT_CLK(NULL, "gpu_core_gclk_mux", "gpu_core_gclk_mux"),
 	DT_CLK(NULL, "gpu_hyd_gclk_mux", "gpu_hyd_gclk_mux"),