Added missing includes to avoid warnings/errors.

diff --git a/server/device.c b/server/device.c
index 3ded814..83446f4 100644
--- a/server/device.c
+++ b/server/device.c
@@ -17,7 +17,7 @@
 #include <string.h>
 
 #include "winerror.h"
-#include "winnt.h"
+#include "winbase.h"
 #include "server/thread.h"
 
 struct device
diff --git a/server/file.c b/server/file.c
index 3c5e816..e624998 100644
--- a/server/file.c
+++ b/server/file.c
@@ -18,7 +18,7 @@
 #include <utime.h>
 
 #include "winerror.h"
-#include "winnt.h"
+#include "winbase.h"
 #include "server/thread.h"
 
 struct file
diff --git a/server/pipe.c b/server/pipe.c
index 1f92d10..06260f9 100644
--- a/server/pipe.c
+++ b/server/pipe.c
@@ -17,7 +17,7 @@
 #include <unistd.h>
 
 #include "winerror.h"
-#include "winnt.h"
+#include "winbase.h"
 #include "server/thread.h"
 
 enum side { READ_SIDE, WRITE_SIDE };
diff --git a/server/thread.c b/server/thread.c
index 5e5e3d6..5bf2f70 100644
--- a/server/thread.c
+++ b/server/thread.c
@@ -13,8 +13,10 @@
 #include <sys/types.h>
 #include <sys/uio.h>
 #include <unistd.h>
+#include <stdarg.h>
 
-#include "winnt.h"
+
+#include "winbase.h"
 #include "winerror.h"
 #include "server.h"
 #include "server/thread.h"