allow forcibly creating metadata on buckets (#14820)

introduce x-minio-force-create environment variable
to force create a bucket and its metadata as required,
it is useful in some situations when bucket metadata
needs recovery.

cmd/object-api-interface.go

@@ -98,6 +98,7 @@ type BucketOptions struct {
 	Location          string
 	LockEnabled       bool
 	VersioningEnabled bool
+	ForceCreate       bool // Create buckets even if they are already created.
 }
 
 // DeleteBucketOptions provides options for DeleteBucket calls.