patch 8.2.0590: no 'backspace' value allows ignoring the insertion point

Problem:    No 'backspace' value allows ignoring the insertion point.
Solution:   Add the "nostop" and 3 values. (Christian Brabandt, closes #5940)
diff --git a/src/edit.c b/src/edit.c
index edd2374..3f0803f 100644
--- a/src/edit.c
+++ b/src/edit.c
@@ -4884,8 +4884,10 @@
 		    revins_on ||
 #endif
 		    (curwin->w_cursor.col > mincol
-		    && (curwin->w_cursor.lnum != Insstart_orig.lnum
-			|| curwin->w_cursor.col != Insstart_orig.col)));
+		    &&  (can_bs(BS_NOSTOP)
+			|| (curwin->w_cursor.lnum != Insstart_orig.lnum
+			|| curwin->w_cursor.col != Insstart_orig.col)
+		    )));
 	}
 	did_backspace = TRUE;
     }