doc/sdk-cli-reference.md: add --write-config to and modify --csv-config in 'olm-catalog gen-csv'

Author: estroz

doc/sdk-cli-reference.md

@@ -188,7 +188,8 @@ Writes a Cluster Service Version (CSV) manifest and optionally CRD files to `dep
 
 * `--csv-version` string - (required) Semantic version of the CSV manifest.
 * `--from-version` string - Semantic version of CSV manifest to use as a base for a new version.
-* `--csv-config` string - Path to CSV config file. Defaults to deploy/olm-catalog/csv-config.yaml.
+* `--csv-config` string - Path to CSV config file. Set --write-config to write a new default config to path. Default path is deploy/olm-catalog/csv-config.yaml.
+* `--write-config` Write a default CSV config file. Set --csv-config=<path> to supply a non-default path. Default path is deploy/olm-catalog/csv-config.yaml.
 * `--update-crds` Update CRD manifests in deploy/{operator-name}/{csv-version} using the latest CRD manifests.
 
 #### Example