Remove redundant memory initialization

When memory is allocated it is also initialized with 0.

Signed-off-by: Gabor Mezei <gabor.mezei@arm.com>
diff --git a/tests/suites/test_suite_mpi.function b/tests/suites/test_suite_mpi.function
index 985801b..bfadde9 100644
--- a/tests/suites/test_suite_mpi.function
+++ b/tests/suites/test_suite_mpi.function
@@ -919,7 +919,6 @@
     ASSERT_ALLOC( Y, len );
 
     ASSERT_ALLOC( buff_m, len );
-    memset( buff_m, 0, len );
     mbedtls_mpi_mod_modulus_init( &m );
     TEST_ASSERT( mbedtls_mpi_mod_modulus_setup(
                         &m, buff_m, copy_limbs,
@@ -994,7 +993,6 @@
     ASSERT_ALLOC( tmp_Y, len );
 
     ASSERT_ALLOC( buff_m, input_len );
-    memset( buff_m, 0, input_len );
     mbedtls_mpi_mod_modulus_init( &m );
     TEST_ASSERT( mbedtls_mpi_mod_modulus_setup(
                         &m, buff_m, copy_limbs,