Remove cyclic inclusion and unused headers.

gcc/rust/ChangeLog:

	* checks/lints/rust-lint-marklive-base.h (RUST_HIR_LIVENESS_BASE):
	Remove header includes.

Signed-off-by: Pierre-Emmanuel Patry <pierre-emmanuel.patry@embecosm.com>

Author: P-E-P

gcc/rust/checks/lints/rust-lint-marklive-base.h

@@ -19,9 +19,6 @@
 #ifndef RUST_HIR_LIVENESS_BASE
 #define RUST_HIR_LIVENESS_BASE
 
-#include "rust-diagnostics.h"
-#include "rust-lint-marklive.h"
-#include "rust-lint-marklive-base.h"
 #include "rust-hir-visitor.h"
 #include "rust-hir-map.h"