Add compile time initilaizers to ECDH and bignum structs

Signed-off-by: Waleed Elmelegy <waleed.elmelegy@arm.com>
diff --git a/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h b/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h
index b340614..f4fc892 100644
--- a/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h
+++ b/tf-psa-crypto/drivers/builtin/include/mbedtls/ecp.h
@@ -255,6 +255,7 @@
 #define MBEDTLS_ECP_GROUP_INIT { MBEDTLS_ECP_DP_NONE, MBEDTLS_MPI_INIT, MBEDTLS_MPI_INIT, \
                                  MBEDTLS_MPI_INIT, MBEDTLS_ECP_POINT_INIT, MBEDTLS_MPI_INIT, \
                                  0, 0, 0, NULL, NULL, NULL, NULL, NULL, 0 }
+
 /**
  * \name SECTION: Module settings
  *
@@ -372,6 +373,8 @@
     mbedtls_ecp_restart_muladd_ctx *MBEDTLS_PRIVATE(ma); /*!<  ecp_muladd() sub-context      */
 } mbedtls_ecp_restart_ctx;
 
+#define MBEDTLS_ECP_RESTART_INIT {0, 0, NULL, NULL}
+
 /*
  * Operation counts for restartable functions
  */