Added bed corners to bed icon.

- This makes it look less like a dash (idea stolen from cjsoong).

Marlin/src/lcd/dogm/status_screen_lite_ST7920.h

@@ -266,16 +266,15 @@ const uint16_t bed_icon[] PROGMEM = {
   0b0000000000000000,
   0b0000000000000000,
   0b0000000000000000,
-  0b0000000000000000,
   0b0111111111111110,
   0b0111111111111110,
+  0b0110000000000110,
   0b0000000000000000,
   0b0000000000000000
 };
 
 const uint16_t heat1_icon[] PROGMEM = {
   0b0000000000000000,
-  0b0000000000000000,
   0b0010001000100000,
   0b0001000100010000,
   0b0000100010001000,
@@ -289,12 +288,12 @@ const uint16_t heat1_icon[] PROGMEM = {
   0b0000000000000000,
   0b0000000000000000,
   0b0000000000000000,
+  0b0000000000000000,
   0b0000000000000000
 };
 
 const uint16_t heat2_icon[] PROGMEM = {
   0b0000000000000000,
-  0b0000000000000000,
   0b0000100010001000,
   0b0000100010001000,
   0b0001000100010000,
@@ -308,6 +307,7 @@ const uint16_t heat2_icon[] PROGMEM = {
   0b0000000000000000,
   0b0000000000000000,
   0b0000000000000000,
+  0b0000000000000000,
   0b0000000000000000
 };