patch 8.0.1295: cannot automatically get a server name in a terminal

Problem:    Cannot automatically get a server name in a terminal.
Solution:   Add the --enable-autoservername flag to configure. (Cimbali,
            closes #2317)
diff --git a/src/evalfunc.c b/src/evalfunc.c
index 5e22fe4..1991aa7 100644
--- a/src/evalfunc.c
+++ b/src/evalfunc.c
@@ -5580,6 +5580,9 @@
 #ifdef FEAT_AUTOCMD
 	"autocmd",
 #endif
+#ifdef FEAT_AUTOSERVERNAME
+	"autoservername",
+#endif
 #ifdef FEAT_BEVAL
 	"balloon_eval",
 # ifndef FEAT_GUI_W32 /* other GUIs always have multiline balloons */