build: remove unused code spotted by the deadcode linter

backend/pcloud/pcloud.go

@@ -17,7 +17,6 @@ import (
 	"net/http"
 	"net/url"
 	"path"
-	"regexp"
 	"strings"
 	"time"
 
@@ -130,9 +129,6 @@ func (f *Fs) Features() *fs.Features {
 	return f.features
 }
 
-// Pattern to match a pcloud path
-var matcher = regexp.MustCompile(`^([^/]*)(.*)$`)
-
 // parsePath parses an pcloud 'url'
 func parsePath(path string) (root string) {
 	root = strings.Trim(path, "/")