Move os/arch/compiler headers into directories

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/fio.h b/fio.h
index a62971d..6b70805 100644
--- a/fio.h
+++ b/fio.h
@@ -13,13 +13,13 @@
 #include <string.h>
 #include <getopt.h>
 
-#include "compiler.h"
+#include "compiler/compiler.h"
 #include "list.h"
 #include "rbtree.h"
 #include "md5.h"
 #include "crc32.h"
-#include "arch.h"
-#include "os.h"
+#include "arch/arch.h"
+#include "os/os.h"
 #include "mutex.h"
 
 #ifdef FIO_HAVE_SYSLET