mbedtls_mpi_mod_raw_inv_prime() tests should be arch_split

Signed-off-by: Tom Cosgrove <tom.cosgrove@arm.com>
diff --git a/scripts/mbedtls_dev/bignum_mod_raw.py b/scripts/mbedtls_dev/bignum_mod_raw.py
index 6fc4c91..0084898 100644
--- a/scripts/mbedtls_dev/bignum_mod_raw.py
+++ b/scripts/mbedtls_dev/bignum_mod_raw.py
@@ -61,7 +61,7 @@
     symbol = "^ -1"
     test_function = "mpi_mod_raw_inv_prime"
     test_name = "mbedtls_mpi_mod_raw_inv_prime (Montgomery form only)"
-    input_style = "fixed"
+    input_style = "arch_split"
     arity = 1
     suffix = True