Fix jumping progress bar. (#11439)

- When LCD_SET_PROGRESS_MANUALLY was disabled and an SD print was not active (i.e. the printer was idle), progress_bar_percent would read uninitialized memory from stack and cause progress bar to jump wildly.
- Also updated conditions in `#ifdef` to match `ultralcd.cpp`

Marlin/src/lcd/dogm/status_screen_lite_ST7920.h

@@ -877,11 +877,11 @@ void ST7920_Lite_Status_Screen::update_status_or_position(bool forceUpdate) {
 
 void ST7920_Lite_Status_Screen::update_progress(const bool forceUpdate) {
   #if DISABLED(LCD_SET_PROGRESS_MANUALLY)
-    uint8_t progress_bar_percent;
+    uint8_t progress_bar_percent = 0;
   #endif
 
-  // Set current percentage from SD when actively printing
-  #if ENABLED(SDSUPPORT)
+  #if ENABLED(LCD_SET_PROGRESS_MANUALLY) && ENABLED(SDSUPPORT) && (ENABLED(LCD_PROGRESS_BAR) || ENABLED(DOGLCD))
+    // Progress bar % comes from SD when actively printing
     if (IS_SD_PRINTING) progress_bar_percent = card.percentDone();
   #endif