[Fix](Variant) fix variant predicate rewrite OrToIn with wrong plan

fe/fe-core/src/main/java/org/apache/doris/analysis/SlotRef.java

@@ -540,6 +540,9 @@ public boolean hasCol() {
     }
 
     public String getColumnName() {
+        if (subColPath != null && !subColPath.isEmpty()) {
+            return col + "." + String.join(".", subColPath);
+        }
         return col;
     }
 

regression-test/data/variant_p0/sql/rewrite_or_to_in.out

@@ -0,0 +1,12 @@
+-- This file is automatically generated. You should know what you did if you want to edit this
+-- !rewrite_or_to_in --
+0
+
+-- !rewrite_or_to_in_2 --
+DeleteEvent	megan777/calculator	2021-01-02T16:37:26Z
+DeleteEvent	megan777/calculator	2021-01-02T16:37:26Z
+DeleteEvent	megan777/calculator	2021-01-02T16:37:27Z
+PushEvent	megan777/calculator	2021-01-02T16:39:09Z
+CreateEvent	megan777/calculator	2021-01-02T16:39:41Z
+PullRequestEvent	megan777/calculator	2021-01-02T16:39:41Z
+

regression-test/suites/variant_p0/sql/rewrite_or_to_in.sql

@@ -0,0 +1,6 @@
+set rewrite_or_to_in_predicate_threshold = 2;
+select
+    cast(v:type as string), cast(v:repo.name as string), cast(v:created_at as string)
+from ghdata
+where cast(v:type as string) = 'Delete' or cast(v:repo.name as string) = 'megan777/calculator' or cast(v:created_as as string) = '2021-01-02T16:37:26Z'
+order by k limit 10;