CI: Adjust codecov.io configuration

Disable statuses and PR comments, make precision and ranges match lcov
reports generated by 'make coverage-report', remove unnecessary
contents. Rename codecov.yml -> .codecov.yml

.codecov.yml

@@ -0,0 +1,20 @@
+---
+# DESCRIPTION: codecov.io config
+#
+# Copyright 2020-2025 by Wilson Snyder. This program is free software; you
+# can redistribute it and/or modify it under the terms of either the GNU
+# Lesser General Public License Version 3 or the Perl Artistic License
+# Version 2.0.
+# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
+####################
+# Validate:
+#  curl --data-binary @.codecov.yml https://codecov.io/validate
+#
+coverage:
+  precision: 2
+  range: 75...100
+  round: down
+  status:
+    project: off
+    patch: off
+comment: false

codecov.yml

@@ -1,36 +0,0 @@
----
-# DESCRIPTION: codecov.io config
-#
-# Copyright 2020-2025 by Wilson Snyder. This program is free software; you
-# can redistribute it and/or modify it under the terms of either the GNU
-# Lesser General Public License Version 3 or the Perl Artistic License
-# Version 2.0.
-# SPDX-License-Identifier: LGPL-3.0-only OR Artistic-2.0
-####################
-# Validate:
-#  curl --data-binary @codecov.yml https://codecov.io/validate
-#
-codecov:
-  require_ci_to_pass: false
-coverage:
-  precision: 2
-  round: down
-  range: 50...100
-  ignore:
-    - "ci"  #
-    - "docs"  #
-    - "examples"  #
-    - "include/gtkwave"  #
-    - "include/vltstd"  #
-    - "test_regress"  #
-parsers:
-  gcov:
-    branch_detection:
-      conditional: true
-      loop: true
-      method: false
-      macro: false
-comment:
-  layout: "reach,diff,flags,tree"
-  behavior: default
-  require_changes: true