winedbg: Push the correct machine type to StackWalk.

programs/winedbg/be_i386.c

diff --git a/programs/winedbg/be_i386.c b/programs/winedbg/be_i386.c
index e3e7a81..e805a80 100644
--- a/programs/winedbg/be_i386.c
+++ b/programs/winedbg/be_i386.c
@@ -746,6 +746,7 @@
 
 struct backend_cpu be_i386 =
 {
+    IMAGE_FILE_MACHINE_I386,
     be_i386_linearize,
     be_i386_build_addr,
     be_i386_get_addr,