patch 8.2.0274: hang with combination of feedkeys(), Ex mode and :global

Problem:    Hang with combination of feedkeys(), Ex mode and :global.
            (Yegappan Lakshmanan)
Solution:   Add the pending_exmode_active flag.
diff --git a/src/getchar.c b/src/getchar.c
index d056bcc..b828c27 100644
--- a/src/getchar.c
+++ b/src/getchar.c
@@ -3041,6 +3041,10 @@
 #ifdef FEAT_CMDWIN
 		    tc = c;
 #endif
+		    // return from main_loop()
+		    if (pending_exmode_active)
+			exmode_active = EXMODE_NORMAL;
+
 		    break;
 		}