libgimpconfig: remove negative value handling from gimp_scanner_parse_color()

Handled internally by gimp_scanner_parse_float(), since last commit.

libgimpconfig/gimpscanner.c

@@ -704,19 +704,8 @@ gimp_scanner_parse_color (GScanner *scanner,
 
             for (i = 0; i < n_channels; i++)
               {
-                gboolean negate = FALSE;
-
-                if (g_scanner_peek_next_token (scanner) == '-')
-                  {
-                    negate = TRUE;
-                    g_scanner_get_next_token (scanner);
-                  }
-
                 if (! gimp_scanner_parse_float (scanner, &col[i]))
                   goto finish;
-
-                if (negate)
-                  col[i] = - col[i];
               }
 
             if (is_hsv)