new_variant: remove cb_variant from cq-depend

The cq-depend line can only specify CLs on the chromium or
chrome-internal gerrit instances. The 'cb_variant' step is a CL in
the coreboot gerrit, so remove it from the depends list for all
variants that use coreboot.org.
For Zork variants that are using coreboot-zork, remove the 'find'
step, as this step looks for an upstream CL that we won't have on
Zork for now.
To ensure that `git filter-branch` (which adds the Cq-Depend line)
will succeed, add the -f option so that remnants of previous
filter-branch operations won't cause a failure.

BUG=b:159812946
TEST=create a new variant and get it to the add_cq_depend step. Verify
that the fw_build_config CL does not include a CL in its cq-depend
line that starts with coreboot:

Change-Id: Ia59d69df40413ad4bc288f9bd5524641996ee7f0
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/2264519
Tested-by: Paul Fagerburg <pfagerburg@chromium.org>
Commit-Queue: Paul Fagerburg <pfagerburg@chromium.org>
Reviewed-by: Jack Rosenthal <jrosenth@chromium.org>
diff --git a/contrib/variant/new_variant.py b/contrib/variant/new_variant.py
index 3cc4220..0a4ef50 100755
--- a/contrib/variant/new_variant.py
+++ b/contrib/variant/new_variant.py
@@ -1459,6 +1459,7 @@
     cmd = [
         'git',
         'filter-branch',
+        '-f',
         '--msg-filter',
         f'sed -E "s/^(Change-Id: {change_id})$/{cq_depend_str}\\n\\1/"',
         '--',
diff --git a/contrib/variant/puff.py b/contrib/variant/puff.py
index c7ae3a0..84b1eca 100644
--- a/contrib/variant/puff.py
+++ b/contrib/variant/puff.py
@@ -90,6 +90,5 @@
 depends = {
     step_names.CB_CONFIG: [step_names.FIND],
     step_names.FW_BUILD_CONFIG: [
-        step_names.FIND, step_names.CB_VARIANT, step_names.CB_CONFIG,
-        step_names.COMMIT_FIT]
+        step_names.FIND, step_names.CB_CONFIG, step_names.COMMIT_FIT]
 }
diff --git a/contrib/variant/trembyle.py b/contrib/variant/trembyle.py
index 6301d16..00f0fef 100644
--- a/contrib/variant/trembyle.py
+++ b/contrib/variant/trembyle.py
@@ -70,6 +70,6 @@
 depends = {
     step_names.CB_CONFIG: [step_names.CB_VARIANT],
     step_names.FW_BUILD_CONFIG: [
-        step_names.FIND, step_names.CB_VARIANT, step_names.CB_CONFIG,
+        step_names.CB_VARIANT, step_names.CB_CONFIG,
         step_names.CRAS_CONFIG, step_names.EC_IMAGE, step_names.COMMIT_FIT]
 }
diff --git a/contrib/variant/volteer.py b/contrib/variant/volteer.py
index c1b309a..a8b4ab0 100644
--- a/contrib/variant/volteer.py
+++ b/contrib/variant/volteer.py
@@ -84,6 +84,6 @@
 depends = {
     step_names.CB_CONFIG: [step_names.FIND],
     step_names.FW_BUILD_CONFIG: [
-        step_names.FIND, step_names.CB_VARIANT, step_names.CB_CONFIG,
+        step_names.FIND, step_names.CB_CONFIG,
         step_names.COMMIT_FIT, step_names.EC_IMAGE]
 }
diff --git a/contrib/variant/waddledee.py b/contrib/variant/waddledee.py
index 75cc82b..b187a62 100644
--- a/contrib/variant/waddledee.py
+++ b/contrib/variant/waddledee.py
@@ -84,6 +84,6 @@
 depends = {
     step_names.CB_CONFIG: [step_names.FIND],
     step_names.FW_BUILD_CONFIG: [
-        step_names.FIND, step_names.CB_VARIANT, step_names.CB_CONFIG,
+        step_names.FIND, step_names.CB_CONFIG,
         step_names.COMMIT_FIT, step_names.EC_IMAGE]
 }