Fix LMS and LMOTS test dependencies

Mark them as depending on PSA_WANT_ALG_SHA256 so that
test_depends_hashes_psa doesn't fail

Signed-off-by: Raef Coles <raef.coles@arm.com>
diff --git a/tests/suites/test_suite_lms.function b/tests/suites/test_suite_lms.function
index 4e525c4..4f49e8e 100644
--- a/tests/suites/test_suite_lms.function
+++ b/tests/suites/test_suite_lms.function
@@ -4,7 +4,7 @@
 /* END_HEADER */
 
 /* BEGIN_DEPENDENCIES
- * depends_on:MBEDTLS_LMS_C
+ * depends_on:MBEDTLS_LMS_C:PSA_WANT_ALG_SHA_256
  * END_DEPENDENCIES
  */