Add raw key format, for symmetric key import.

Change-Id: I38700cdafcf1f244584d6e88f8d9540c70a7de56
diff --git a/include/hardware/keymaster_defs.h b/include/hardware/keymaster_defs.h
index b351aa4..4649055 100644
--- a/include/hardware/keymaster_defs.h
+++ b/include/hardware/keymaster_defs.h
@@ -359,6 +359,7 @@
     KM_KEY_FORMAT_X509,   /* for public key export, required */
     KM_KEY_FORMAT_PKCS8,  /* for asymmetric key pair import, required */
     KM_KEY_FORMAT_PKCS12, /* for asymmetric key pair import, not required */
+    KM_KEY_FORMAT_RAW,    /* for symmetric key import, required */
 } keymaster_key_format_t;
 
 /**