ARM: dts: dra71-evm: Use pinctrl group from dra7-mmc-iodelay.dtsi to select pulldown

commit 0e43884c ("ARM: dts: dra71-evm: Select pull
down for mmc1_clk line in default mode") modified mmc1_pins_default
pinctrl group in dra71-evm.dts to change the CLK line to
PIN_INPUT_PULLDOWN. However instead of changing the pinctrl group,
use the new pinctrl group "mmc1_pins_default_no_clk_pu" in
dra7-mmc-iodelay.dtsi added specifically to be used for CLK line
without external pull up.

Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>