patch 8.0.1506: new version of HP NonStop (Tandem) doesn't like a header

Problem:    New version of HP NonStop (Tandem) doesn't like the default header
            for setenv().
Solution:   Put a #ifdef around the setenv() entry. (Joachim Schmitz)
diff --git a/src/version.c b/src/version.c
index cb7ba18..afe8b24 100644
--- a/src/version.c
+++ b/src/version.c
@@ -772,6 +772,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    1506,
+/**/
     1505,
 /**/
     1504,