patch 9.1.1248: compile error when building without FEAT_QUICKFIX

Problem:  compile error when building without FEAT_QUICKFIX
Solution: adjust ifdefs in popupwin.c, add CheckFeature quickfix
          to a few tests (John Marriott, Hirohito Higashi)

closes: #16940
closes: #16962

Co-authored-by: Hirohito Higashi <h.east.727@gmail.com>
Co-authored-by: Zoltan Arpadffy <zoltan.arpadffy@gmail.com>
Co-authored-by: zeertzjq <zeertzjq@outlook.com>
Signed-off-by: John Marriott <basilisk@internode.on.net>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/src/testdir/test_vim9_script.vim b/src/testdir/test_vim9_script.vim
index b29f3cd..d9013dd 100644
--- a/src/testdir/test_vim9_script.vim
+++ b/src/testdir/test_vim9_script.vim
@@ -1226,6 +1226,7 @@
 enddef
 
 def Test_cnext_works_in_catch()
+  CheckFeature quickfix
   var lines =<< trim END
       vim9script
       au BufEnter * eval 1 + 2
@@ -1541,6 +1542,7 @@
 enddef
 
 def Test_cexpr_vimscript()
+  CheckFeature quickfix
   # only checks line continuation
   set errorformat=File\ %f\ line\ %l
   var lines =<< trim END
@@ -3991,6 +3993,7 @@
 endfunc
 
 def Test_vim9_copen()
+  CheckFeature quickfix
   # this was giving an error for setting w:quickfix_title
   copen
   quit