ntdll: Add missing check for DragonFly BSD

[André Hentschel]

Dragonfly BSD has some issues at compiletime, most times because of their headers or API changes.
atm iphlpapi and ws2_32(and /tests) doesn't compile and ntdll only does with some hacks.
the only clean thing i added to make it compile was this patch, so maybe it's a start.
(but it's no general thing to add dragonfly where freebsd_kernel is added)
---
 dlls/ntdll/signal_i386.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/dlls/ntdll/signal_i386.c b/dlls/ntdll/signal_i386.c
index 13444ae..6c8e8e2 100644
--- a/dlls/ntdll/signal_i386.c
+++ b/dlls/ntdll/signal_i386.c
@@ -208,7 +208,7 @@ typedef struct trapframe SIGCONTEXT;
 
 #endif /* bsdi */
 
-#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__)
+#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
 
 #include <machine/trap.h>
 
-- 

Best Regards, André Hentschel