Remove undesirable test

Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
diff --git a/tests/suites/test_suite_bignum_core.function b/tests/suites/test_suite_bignum_core.function
index 0cd1507..53aa002 100644
--- a/tests/suites/test_suite_bignum_core.function
+++ b/tests/suites/test_suite_bignum_core.function
@@ -301,11 +301,7 @@
     mbedtls_mpi_uint *X = NULL;
     size_t limbs;
 
-    if (strlen(input_X) == 0) {
-        limbs = 0;
-    } else {
-        TEST_EQUAL(mbedtls_test_read_mpi_core(&X, &limbs, input_X), 0);
-    }
+    TEST_EQUAL(mbedtls_test_read_mpi_core(&X, &limbs, input_X), 0);
     TEST_EQUAL(mbedtls_mpi_core_bitlen(X, limbs), nr_bits);
 
 exit:
diff --git a/tests/suites/test_suite_bignum_core.misc.data b/tests/suites/test_suite_bignum_core.misc.data
index 9e1b892..ba86029 100644
--- a/tests/suites/test_suite_bignum_core.misc.data
+++ b/tests/suites/test_suite_bignum_core.misc.data
@@ -155,9 +155,6 @@
 Test mbedtls_mpi_core_bitlen 0x0a
 mpi_core_bitlen:"a":4
 
-Test mbedtls_mpi_core_bitlen: 0 limbs
-mpi_core_bitlen:"":0
-
 Test mbedtls_mpi_core_bitlen: 0 (1 limb)
 mpi_core_bitlen:"0":0