x86, um: untangle uml ldt.h

* turn asm/ldt.h into ldt.h; update the (very few) users
* take host_ldt.h into sysdep, kill symlink mess
* includes of asm/arch/ldt.h turn into asm/ldt.h now

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
diff --git a/arch/um/include/asm/processor-i386.h b/arch/um/include/asm/processor-i386.h
index 4f8be00..82a9061 100644
--- a/arch/um/include/asm/processor-i386.h
+++ b/arch/um/include/asm/processor-i386.h
@@ -7,7 +7,7 @@
 #define __UM_PROCESSOR_I386_H
 
 #include "linux/string.h"
-#include "asm/host_ldt.h"
+#include <sysdep/host_ldt.h>
 #include "asm/segment.h"
 
 extern int host_has_cmov;