Build: Reintroduce PS_TEST_NV_COUNTERS variable

Restores the PS_TEST_NV_COUNTERS build variable, used to enable the
test NV counters implementation, and the Protected Storage rollback
tests.

Change-Id: Ibb1ddbb456118d647409fad1770705990089ba1c
Signed-off-by: Jamie Fox <jamie.fox@arm.com>
diff --git a/config/config_default.cmake b/config/config_default.cmake
index be02017..340eff5 100644
--- a/config/config_default.cmake
+++ b/config/config_default.cmake
@@ -112,6 +112,8 @@
 set(TFM_IRQ_TEST                        OFF         CACHE BOOL      "Enable IRQ tests")
 set(TFM_PERIPH_ACCESS_TEST              OFF         CACHE BOOL      "Enable peripheral access tests")
 
+set(PS_TEST_NV_COUNTERS                 OFF         CACHE BOOL      "Use the test NV counters to test Protected Storage rollback scenarios")
+
 set(TFM_CRYPTO_TEST_ALG_CBC             ON          CACHE BOOL      "Test CBC cryptography mode")
 set(TFM_CRYPTO_TEST_ALG_CCM             ON          CACHE BOOL      "Test CCM cryptography mode")
 set(TFM_CRYPTO_TEST_ALG_CFB             ON          CACHE BOOL      "Test CFB cryptography mode")