Minimize and permit sandbox includes from crypto_ops.

src/lib/crypt_ops/.may_include

@@ -7,6 +7,7 @@ lib/defs/*.h
 lib/malloc/*.h
 lib/err/*.h
 lib/intmath/*.h
+lib/sandbox/*.h
 lib/string/*.h
 lib/testsupport/testsupport.h
 lib/log/*.h

src/lib/crypt_ops/crypto.c

@@ -67,7 +67,6 @@ ENABLE_GCC_WARNING(redundant-decls)
 #include "lib/crypt_ops/aes.h"
 #include "common/util.h"
 #include "common/compat.h"
-#include "lib/sandbox/sandbox.h"
 #include "common/util_format.h"
 
 #include "keccak-tiny/keccak-tiny.h"