ANDROID: cuttlefish_defconfig: Drop built-in cmdline (except nopti)

This fixes duplicate kernel log messages. Only earlycon from ttyS0
should be logged, after virtio-console is loaded it should come only
from there.

Bug: 160341724
Change-Id: I194343fcaff822b31c8d8b6138196cb4e077613c
Signed-off-by: Alistair Delva <adelva@google.com>