ARM: imx: Introduce DH i.MX6 DHSOM board specific defconfigs

Move content of dh_imx6_defconfig into dh_imx6.config. Retain legacy
dh_imx6_defconfig as multi-config for all DH i.MX6 DHSOM based boards.
Introduce separate imx6_dhcom_drc02_defconfig, imx6_dhcom_pdk2_defconfig
and imx6_dhcom_picoitx_defconfig for each i.MX6 DHSOM based board, to
make build for those boards easier. No functional change.

Signed-off-by: Marek Vasut <marex@denx.de>
5 files changed