patch 9.1.1338: Calling expand() interferes with cmdcomplete_info()

Problem:  Calling expand() interferes with cmdcomplete_info()
          (after 9.1.1329).
Solution: Only clear cmdline_orig when starting/ending cmdline mode
          (zeertzjq).

closes: #17192

Signed-off-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/cmdexpand.c b/src/cmdexpand.c
index e8bc080..4dbd10e 100644
--- a/src/cmdexpand.c
+++ b/src/cmdexpand.c
@@ -1115,7 +1115,6 @@
     xp->xp_backslash = XP_BS_NONE;
     xp->xp_prefix = XP_PREFIX_NONE;
     xp->xp_numfiles = -1;
-    VIM_CLEAR(cmdline_orig);
 }
 
 /*
@@ -1132,6 +1131,12 @@
     VIM_CLEAR(xp->xp_orig);
 }
 
+    void
+clear_cmdline_orig(void)
+{
+    VIM_CLEAR(cmdline_orig);
+}
+
 /*
  * Display one line of completion matches. Multiple matches are displayed in
  * each line (used by wildmode=list and CTRL-D)