Added PLOOPY_DRAGSCROLL_H_INVERT (#17453)

keyboards/ploopyco/trackball/trackball.c

@@ -119,7 +119,12 @@ report_mouse_t pointing_device_task_kb(report_mouse_t mouse_report) {
     process_wheel();
 
     if (is_drag_scroll) {
+#ifdef PLOOPY_DRAGSCROLL_H_INVERT
+        // Invert horizontal scroll direction
+        mouse_report.h = -mouse_report.x;
+#else
         mouse_report.h = mouse_report.x;
+#endif
 #ifdef PLOOPY_DRAGSCROLL_INVERT
         // Invert vertical scroll direction
         mouse_report.v = -mouse_report.y;