Build: Enable PS rollback tests

Enables the Protected Storage rollback tests, and the test NV counters
they use, when the PS_TEST_NV_COUNTERS build variable is ON.

Change-Id: I111324a757b7c07f804b74a38f1ac792e72cfbe6
Signed-off-by: Jamie Fox <jamie.fox@arm.com>
diff --git a/test/CMakeLists.txt b/test/CMakeLists.txt
index 6803644..c7aaf27 100644
--- a/test/CMakeLists.txt
+++ b/test/CMakeLists.txt
@@ -85,3 +85,8 @@
         tfm_partition_defs
         tfm_spm
 )
+
+target_compile_definitions(tfm_s_tests
+    INTERFACE
+        $<$<BOOL:${PS_TEST_NV_COUNTERS}>:PS_TEST_NV_COUNTERS>
+)