patch 8.1.0791: a few compiler warnings on VMS

Problem:    A few compiler warnings on VMS.
Solution:   Remove type cast.  Adjust #ifdef. (Zoltan Arpadffy)
diff --git a/src/os_unix.c b/src/os_unix.c
index 33ef781..3757dc5 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -1935,7 +1935,7 @@
 	alarm(0);
 	signal(SIGALRM, (RETSIGTYPE (*)())sig_save);
 	if (p_verbose > 0 && sig_alarm_called)
-	    verb_msg((char_u *)_("Opening the X display timed out"));
+	    verb_msg(_("Opening the X display timed out"));
 #endif
 	if (x11_display != NULL)
 	{
diff --git a/src/proto.h b/src/proto.h
index 0bac087..a71b632 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -256,7 +256,7 @@
 # endif
 
 # if defined(FEAT_GUI) || defined(FEAT_JOB_CHANNEL)
-#  if defined(UNIX) || defined(MACOS_X)
+#  if defined(UNIX) || defined(MACOS_X) || defined(VMS)
 #   include "pty.pro"
 #  endif
 # endif
diff --git a/src/version.c b/src/version.c
index 8d2050f..f33f850 100644
--- a/src/version.c
+++ b/src/version.c
@@ -792,6 +792,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    791,
+/**/
     790,
 /**/
     789,