Reorder includes in Target backends to following coding standards. Remove some superfluous forward declarations.

llvm-svn: 152997
diff --git a/llvm/lib/Target/Sparc/SparcISelLowering.h b/llvm/lib/Target/Sparc/SparcISelLowering.h
index 4a7c479..f483c96 100644
--- a/llvm/lib/Target/Sparc/SparcISelLowering.h
+++ b/llvm/lib/Target/Sparc/SparcISelLowering.h
@@ -15,8 +15,8 @@
 #ifndef SPARC_ISELLOWERING_H
 #define SPARC_ISELLOWERING_H
 
-#include "llvm/Target/TargetLowering.h"
 #include "Sparc.h"
+#include "llvm/Target/TargetLowering.h"
 
 namespace llvm {
   namespace SPISD {