Calling the residue_release() is not needed

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
diff --git a/tests/suites/test_suite_bignum_mod.function b/tests/suites/test_suite_bignum_mod.function
index 6e25ff7..c19c2f4 100644
--- a/tests/suites/test_suite_bignum_mod.function
+++ b/tests/suites/test_suite_bignum_mod.function
@@ -181,10 +181,6 @@
     }
 
 exit:
-    mbedtls_mpi_mod_residue_release( &rA );
-    mbedtls_mpi_mod_residue_release( &rB );
-    mbedtls_mpi_mod_residue_release( &rR );
-    mbedtls_mpi_mod_residue_release( &rX );
     mbedtls_mpi_mod_modulus_free( &m );
 
     mbedtls_free( rA.p );
@@ -237,10 +233,6 @@
                 MBEDTLS_ERR_MPI_BAD_INPUT_DATA );
 
 exit:
-    mbedtls_mpi_mod_residue_release( &rA );
-    mbedtls_mpi_mod_residue_release( &rB );
-    mbedtls_mpi_mod_residue_release( &rR );
-    mbedtls_mpi_mod_residue_release( &rX );
     mbedtls_mpi_mod_modulus_free( &m );
     mbedtls_mpi_mod_modulus_free( &fake_m );