soc: arm: Refactor i.mx rt device configuration data default

Refactors the i.mx rt soc series to enable device configuration data
(DCD) by default when the smart external memory controller (SEMC) is
present. This is in preparation for removing the DATA_LOCATION Kconfig
symbol and using a device tree chosen node instead.

Signed-off-by: Maureen Helm <maureen.helm@nxp.com>