feat(fwu): modify the check for getting the FWU bank's state

The version 2 of the FWU metadata structure has a field bank_state in
the top level of the structure which can be used to check if a given
bank is in the either of Trial State, Accepted State, or in an Invalid
State. This is different from the binary states of Valid/Accepted
States that the bank could be in, as defined in the earlier version of
the specification.

Replace the fwu_is_trial_run_state() API with
fwu_get_active_bank_state() to get the state the current active bank
is in. The value returned by this API is then used by the caller to
take appropriate action.

Change-Id: I764f486840a3713bfe5f8e03d0634bfe09b23590
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
diff --git a/drivers/auth/auth_mod.c b/drivers/auth/auth_mod.c
index 608866c..8c5ff9d 100644
--- a/drivers/auth/auth_mod.c
+++ b/drivers/auth/auth_mod.c
@@ -328,7 +328,6 @@
 	unsigned int data_len, len, i;
 	unsigned int plat_nv_ctr;
 	int rc;
-	bool is_trial_run = false;
 
 	/* Get the counter value from current image. The AM expects the IPM
 	 * to return the counter value as a DER encoded integer */
@@ -388,9 +387,14 @@
 		return 1;
 	} else if (*cert_nv_ctr > plat_nv_ctr) {
 #if PSA_FWU_SUPPORT && IMAGE_BL2
-		is_trial_run = fwu_is_trial_run_state();
+		if (fwu_get_active_bank_state() == FWU_BANK_STATE_ACCEPTED) {
+			*need_nv_ctr_upgrade = true;
+		} else {
+			*need_nv_ctr_upgrade = false;
+		}
+#else
+		*need_nv_ctr_upgrade = true;
 #endif /* PSA_FWU_SUPPORT && IMAGE_BL2 */
-		*need_nv_ctr_upgrade = !is_trial_run;
 	}
 
 	return 0;