Fix an typo that breaks the build when SQLITE_ENABLE_TREE_EXPLAIN is defined.

FossilOrigin-Name: f461e2b3973d0fe6a7b8cb7a3aaab8a30b3e16c0
diff --git a/src/expr.c b/src/expr.c
index 67aae87..aad6cd1 100644
--- a/src/expr.c
+++ b/src/expr.c
@@ -3388,7 +3388,7 @@
       sqlite3ExplainPrintf(pOut, "item[%d] = ", i);
       sqlite3ExplainPush(pOut);
       sqlite3ExplainExpr(pOut, pList->a[i].pExpr);
-      sqlite3ExplainPop(pOut, 1);
+      sqlite3ExplainPop(pOut);
       if( pList->a[i].zName ){
         sqlite3ExplainPrintf(pOut, " AS %s", pList->a[i].zName);
       }