More mbedtls_mpi_bitlen test cases

* with leading zero limb
* with trailing zero limb
* negative

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/tests/suites/test_suite_mpi.data b/tests/suites/test_suite_mpi.data
index 52dee89..d88ae13 100644
--- a/tests/suites/test_suite_mpi.data
+++ b/tests/suites/test_suite_mpi.data
@@ -447,6 +447,12 @@
 Test mbedtls_mpi_bitlen 0x18
 mpi_bitlen:"18":5
 
+Test mbedtls_mpi_bitlen 0x18 with leading 0 limb(s)
+mpi_bitlen:"00000000000000018":5
+
+Test mbedtls_mpi_bitlen 0x18 << 64
+mpi_bitlen:"180000000000000000":69
+
 Test mbedtls_mpi_bitlen 0x01
 mpi_bitlen:"1":1
 
@@ -465,6 +471,9 @@
 Test mbedtls_mpi_bitlen: 0 (1 limb)
 mpi_bitlen:"0":0
 
+Test mbedtls_mpi_bitlen: -0x18
+mpi_bitlen:"-18":5
+
 Base test mbedtls_mpi_cmp_int #1
 mpi_cmp_int:693:693:0