Only use I_PUSH ioctl when I_PUSH is defined.

Fixes compilation on -current.

devel/cgdb/distinfo

@@ -1,5 +1,6 @@
-$NetBSD: distinfo,v 1.2 2005/02/23 22:24:11 agc Exp $
+$NetBSD: distinfo,v 1.3 2005/12/23 16:19:12 wiz Exp $
 
 SHA1 (cgdb-0.4.0.tar.gz) = 900105c73e8c16dec9f3e37343abbba120d36df6
 RMD160 (cgdb-0.4.0.tar.gz) = f79e567ccf96d5d473e1cd4859ac97bc17619f67
 Size (cgdb-0.4.0.tar.gz) = 471395 bytes
+SHA1 (patch-aa) = 923af14fee3272739126e05ebe591c627ffdd934

devel/cgdb/patches/patch-aa

@@ -0,0 +1,20 @@
+$NetBSD: patch-aa,v 1.1 2005/12/23 16:19:12 wiz Exp $
+
+--- various/util/src/pseudo.c.orig	2003-04-28 02:04:04.000000000 +0200
++++ various/util/src/pseudo.c
+@@ -327,6 +327,7 @@ int pty_open(int *masterfd, int *slavefd
+ 
+ #ifndef HAVE_CYGWIN 
+ #ifndef HAVE_LINUX /* linux does not use the streams module */
++#ifdef I_PUSH
+ 	/*
+ 	 * Push the appropriate streams modules, as described in Solaris pts(7).
+ 	 * HP-UX pts(7) doesn't have ttcompat module.
+@@ -355,6 +356,7 @@ int pty_open(int *masterfd, int *slavefd
+ #endif
+ #endif
+ #endif
++#endif
+ 
+ #else /* HAVE_DEV_PTMX */
+ #ifdef HAVE_DEV_PTS_AND_PTC