Fix linter warnings

internal/backend/http_transport.go

@@ -45,10 +45,7 @@ func readPEMCertKey(filename string) (certs []byte, key []byte, err error) {
 	}
 
 	var block *pem.Block
-	for {
-		if len(data) == 0 {
-			break
-		}
+	for len(data) > 0 {
 		block, data = pem.Decode(data)
 		if block == nil {
 			break

internal/backend/location/location.go

@@ -34,6 +34,7 @@ func isPath(s string) bool {
 
 	// check for drive paths
 	drive := s[0]
+	//nolint:staticcheck // de morgan's law makes this harder to read
 	if !(drive >= 'a' && drive <= 'z') && !(drive >= 'A' && drive <= 'Z') {
 		return false
 	}

internal/backend/rest/rest_int_test.go

@@ -79,8 +79,8 @@ func TestListAPI(t *testing.T) {
 				t.Logf("req %v %v, accept: %v", req.Method, req.URL.Path, req.Header["Accept"])
 
 				var err error
-				switch {
-				case req.Method == "GET":
+				switch req.Method {
+				case "GET":
 					// list files in data/
 					res.Header().Set("Content-Type", test.ContentType)
 					_, err = res.Write([]byte(test.Data))
@@ -89,7 +89,7 @@ func TestListAPI(t *testing.T) {
 						t.Fatal(err)
 					}
 					return
-				case req.Method == "HEAD":
+				case "HEAD":
 					// stat file in data/, use the first two bytes in the name
 					// of the file as the size :)
 					filename := req.URL.Path[6:]