Bignum Mod: remove unused parameter in io_neg test

The value was overwritten and the length wasn't used either. This latter
could have lead to a buffer overflow as well.

Signed-off-by: Janos Follath <janos.follath@arm.com>
diff --git a/tests/suites/test_suite_bignum_mod.data b/tests/suites/test_suite_bignum_mod.data
index 8579bec..2ea4a58 100644
--- a/tests/suites/test_suite_bignum_mod.data
+++ b/tests/suites/test_suite_bignum_mod.data
@@ -57,19 +57,19 @@
 mpi_residue_setup:"fe":"ff":-4
 
 Test mbedtls_mpi_mod_io_neg #1 input_r < modulo m
-mpi_mod_io_neg:"fe":"01":"fd":0
+mpi_mod_io_neg:"fe":"fd":0
 
 Test mbedtls_mpi_mod_io_neg #2  input_r == modulo m
-mpi_mod_io_neg:"fe":"01":"fe":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
+mpi_mod_io_neg:"fe":"fe":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
 
 Test mbedtls_mpi_mod_io_neg #3  input_r > modulo m
-mpi_mod_io_neg:"fe":"01":"ff":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
+mpi_mod_io_neg:"fe":"ff":MBEDTLS_ERR_MPI_BAD_INPUT_DATA
 
 Test mbedtls_mpi_mod_io_neg #4  input_r too large to fit
-mpi_mod_io_neg:"fe":"01":"ffffffffffffffffff":MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
+mpi_mod_io_neg:"fe":"ffffffffffffffffff":MBEDTLS_ERR_MPI_BUFFER_TOO_SMALL
 
 Test mbedtls_mpi_mod_io_neg #5  Sucesfull read / output buffer too small
-mpi_mod_io_neg:"7ffffffffffffffffffffffffffffff1":"7ffffffffffffffffffffffffffffff0":"ffff":0
+mpi_mod_io_neg:"7ffffffffffffffffffffffffffffff1":"ffff":0
 
 Test mbedtls_mpi_mod_io #1 N: "11" A: "119".
 mpi_mod_io:"000000000000000b":"0000000000000000":MBEDTLS_MPI_MOD_EXT_REP_BE