patch 8.2.0929: v:register is not cleared after an operator was executed

Problem:    v:register is not cleared after an operator was executed.
Solution:   Clear v:register after finishing an operator (Andy Massimino,
            closes #5305)
diff --git a/src/normal.c b/src/normal.c
index e352354..ae2c1f5 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -1181,6 +1181,11 @@
 
     msg_nowait = FALSE;
 
+#ifdef FEAT_EVAL
+    if (finish_op)
+	reset_reg_var();
+#endif
+
     // Reset finish_op, in case it was set
 #ifdef CURSOR_SHAPE
     c = finish_op;