plat-imx: remove dependency on CFG_DT=y
plat-imx: remove dependency on CFG_DT=y

Enable IMX to run without a device tree (CFG_DT=n).
The only use of the device tree is for the WDOG driver
to get it's base address.

Tested on Sabre IMX6 and Sabre IMX7.

Reviewed-by: Peng Fan <d3c162a96b7fb54e5d94bc77bc2c7cbbce10806f@nxp.com>
Tested-by: Jordan Rhee <47dce742baa0f83253d225fafd19a7ceeefffbc4@microsoft.com>
Signed-off-by: Jordan Rhee <47dce742baa0f83253d225fafd19a7ceeefffbc4@microsoft.com>

pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os,pascal-brand-st-dev/optee_os