patch 8.0.0577: warning for uninitialized variable

Problem:    Warning for uninitialized variable. (John Marriott)
Solution:   Initialize "indent".
diff --git a/src/version.c b/src/version.c
index b0ccc14..663717b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    577,
+/**/
     576,
 /**/
     575,