init: more header cleanup

Remove includes of "log.h" that really want <android-base/logging.h>
Fix header include order
Remove headers included in .cpp files that their associated .h already includes
Remove some unused headers

Test: boot bullhead
Change-Id: I2b415adfe86a5c8bbe4fb1ebc53c7b0ee2253824
diff --git a/init/log.cpp b/init/log.cpp
index 6b32526..ee6489b 100644
--- a/init/log.cpp
+++ b/init/log.cpp
@@ -17,9 +17,10 @@
 #include "log.h"
 
 #include <fcntl.h>
+#include <linux/audit.h>
 #include <string.h>
 
-#include <linux/audit.h>
+#include <android-base/logging.h>
 #include <netlink/netlink.h>
 #include <selinux/selinux.h>