ChromeOS: Drop filling ECFW_RW/RO state in CNVS

This field was never meant to be filled out by coreboot, because it
can't know what the right value for this will be by the time the OS
is running, so anything coreboot could fill in here is premature.

This field is only read by the chromeos-specific `crossystem` utility,
not by kernel code, so if one does not run through depthcharge there'll
be many more broken assumptions in CNVS anyway.

Change-Id: Ia56b3a3fc82f1b8247a6ee512fe960e9d3d87585
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/63290
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Tim Wawrzynczak <twawrzynczak@chromium.org>

src/include/bootmode.h

@@ -14,7 +14,6 @@ int clear_recovery_mode_switch(void);
 int get_wipeout_mode_switch(void);
 int get_lid_switch(void);
 int get_ec_is_trusted(void);
-bool mainboard_ec_running_ro(void);
 
 /* Return 1 if display initialization is required. 0 if not. */
 int display_init_required(void);