patch 9.0.1388: Amiga: not all builds use gethostname()

Problem:    Amiga: not all builds use gethostname().
Solution:   Use gethostname() for all builds except AROS. (Ola Söder,
            closes #12107)
diff --git a/src/version.c b/src/version.c
index e590919..0a05883 100644
--- a/src/version.c
+++ b/src/version.c
@@ -696,6 +696,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1388,
+/**/
     1387,
 /**/
     1386,