config: Add Dell Latitude E5420

...atches/0038-mb-dell-Add-Latitude-E5420-Sandy-Bridge.patch

config/coreboot/dell9020mt_12mb/config/libgfxinit_corebootfb

config/coreboot/dell9020mt_12mb/config/libgfxinit_txtmode

...ig/coreboot/dell9020sff_12mb/config/libgfxinit_corebootfb

config/coreboot/dell9020sff_12mb/config/libgfxinit_txtmode

config/coreboot/e5420_6mb/config/libgfxinit_corebootfb

config/coreboot/e5420_6mb/config/libgfxinit_txtmode

config/coreboot/e5420_6mb/target.cfg

config/coreboot/e5520_6mb/config/libgfxinit_corebootfb

config/coreboot/e5520_6mb/config/libgfxinit_txtmode

config/coreboot/e5530_12mb/config/libgfxinit_corebootfb

config/coreboot/e5530_12mb/config/libgfxinit_txtmode

config/coreboot/e6420_10mb/config/libgfxinit_corebootfb

config/coreboot/e6420_10mb/config/libgfxinit_txtmode

config/coreboot/e6430_12mb/config/libgfxinit_corebootfb

config/coreboot/e6430_12mb/config/libgfxinit_txtmode

config/coreboot/e6520_10mb/config/libgfxinit_corebootfb

config/coreboot/e6520_10mb/config/libgfxinit_txtmode

config/coreboot/e6530_12mb/config/libgfxinit_corebootfb

config/coreboot/e6530_12mb/config/libgfxinit_txtmode