Do not use output buffer for internal XOR during decryption.

Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
diff --git a/include/mbedtls/ccm.h b/include/mbedtls/ccm.h
index c903e68..06aa6a8 100644
--- a/include/mbedtls/ccm.h
+++ b/include/mbedtls/ccm.h
@@ -61,6 +61,8 @@
 #define MBEDTLS_ERR_CCM_BAD_INPUT       -0x000D
 /** Authenticated decryption failed. */
 #define MBEDTLS_ERR_CCM_AUTH_FAILED     -0x000F
+/** Memory allocation failed */
+#define MBEDTLS_ERR_CCM_ALLOC_FAILED    -0x0011
 
 #ifdef __cplusplus
 extern "C" {