patch 8.0.0355: using uninitialized memory when 'isfname' is empty

Problem:    Using uninitialized memory when 'isfname' is empty.
Solution:   Don't call getpwnam() without an argument. (Dominique Pelle,
            closes #1464)
diff --git a/src/version.c b/src/version.c
index 9494e03..64e1111 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    355,
+/**/
     354,
 /**/
     353,