mediatek: mt7623: remove left-over fragments of mt7623a-rfb-emmc
The image creation for the mt7623a-rfb-emmc has been removed during
a patch refresh without specific comment. The corresponding base-files
entries and DTS patches for 4.14 are still there.
Since mt7623 is pretty dead and nobody has missed this device, let's
just remove the rest.
Fixes: 050da2107a7e ("mediatek: backport upstream mediatek patches")
Signed-off-by: Adrian Schmutzler <freifunk@adrianschmutzler.de>
Acked-by: John Crispin <john@phrozen.org>