Guard tinycrypt files with MBEDTLS_USE_UECC
diff --git a/include/tinycrypt/ecc_dsa.h b/include/tinycrypt/ecc_dsa.h
index aca00bc..8065340 100644
--- a/include/tinycrypt/ecc_dsa.h
+++ b/include/tinycrypt/ecc_dsa.h
@@ -75,6 +75,7 @@
  *          the signer's public key and the signature values (r and s).
  */
 
+#if defined(MBEDTLS_USE_UECC)
 #ifndef __TC_ECC_DSA_H__
 #define __TC_ECC_DSA_H__
 
@@ -137,3 +138,4 @@
 #endif
 
 #endif /* __TC_ECC_DSA_H__ */
+#endif /* MBEDTLS_USE_UECC */