patch 8.1.1432: can't build with eval feature

Problem:    Can't build with eval feature.
Solution:   Add missing rename.
diff --git a/src/evalfunc.c b/src/evalfunc.c
index a6703d1..eaaa1e6 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -813,7 +813,7 @@
     {"popup_close",	1, 1, f_popup_close},
     {"popup_create",	2, 2, f_popup_create},
     {"popup_getoptions", 1, 1, f_popup_getoptions},
-    {"popup_getposition", 1, 1, f_popup_getposition},
+    {"popup_getpos",	1, 1, f_popup_getpos},
     {"popup_hide",	1, 1, f_popup_hide},
     {"popup_move",	2, 2, f_popup_move},
     {"popup_show",	1, 1, f_popup_show},