Re fdo#80538: Remove read-only infobar after "Save As..."

...on a doc in r/o mode, which will switch to the newly saved document in r/w
mode.  Was missing from c6270de9 "fdo#80538 Show
an infobar when document is in read-only mode."

Change-Id: Ie17f4213f989cb4b9d3f7fc114392ec6f516a965

sfx2/source/doc/objserv.cxx

@@ -728,6 +728,7 @@ void SfxObjectShell::ExecFile_Impl(SfxRequest &rReq)
 
             if ( nId == SID_SAVEASDOC  && nErrorCode == ERRCODE_NONE )
             {
+                GetFrame()->RemoveInfoBar("readonly");
                 SetReadOnlyUI(false);
             }