First draft of the sh4 port

src/sh4/lithium-sh4.h

Index: src/sh4/lithium-sh4.h
diff --git a/src/arm/lithium-arm.h b/src/sh4/lithium-sh4.h
similarity index 99%
copy from src/arm/lithium-arm.h
copy to src/sh4/lithium-sh4.h
index 0ba5e45a8fe1c67b99c9e197d89c53a088410fc5..c6e9675f1ed0ad89ef8ef479d4744bb4075f89fd 100644
--- a/src/arm/lithium-arm.h
+++ b/src/sh4/lithium-sh4.h
@@ -25,8 +25,8 @@
 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
-#ifndef V8_ARM_LITHIUM_ARM_H_
-#define V8_ARM_LITHIUM_ARM_H_
+#ifndef V8_SH4_LITHIUM_SH4_H_
+#define V8_SH4_LITHIUM_SH4_H_
 
 #include "hydrogen.h"
 #include "lithium-allocator.h"
@@ -2530,4 +2530,4 @@ class LChunkBuilder BASE_EMBEDDED {
 
 } }  // namespace v8::internal
 
-#endif  // V8_ARM_LITHIUM_ARM_H_
+#endif  // V8_SH4_LITHIUM_SH4_H_