boards: hardkernel: odroid_go: fix SiP variant

Odroid Go uses a custom ESP WROVER-E N16R4, i.e., 16 MB of flash and
4 MB of PSRAM [1].

[1] https://wiki.odroid.com/odroid_go/odroid_go#specifications



Signed-off-by: Gero Schwäricke <gero.schwaericke@posteo.de>