feat(st): get the state of the active bank directly

With version 2 of the FWU metadata structure, the state that a bank is
in can be obtained from the bank_state field in the top level
structure. Read the state of the active bank by referencing this field
directly, instead of making an API call.

Change-Id: Ib22c56acbe172923b1323c544801ded81f1598ec
Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org>
diff --git a/plat/st/common/bl2_io_storage.c b/plat/st/common/bl2_io_storage.c
index 86795d7..96d24d1 100644
--- a/plat/st/common/bl2_io_storage.c
+++ b/plat/st/common/bl2_io_storage.c
@@ -628,7 +628,7 @@
 
 	if (boot_idx == INVALID_BOOT_IDX) {
 		boot_idx = data->active_index;
-		if (fwu_is_trial_run_state()) {
+		if (data->bank_state[boot_idx] == FWU_BANK_STATE_VALID) {
 			if (stm32_get_and_dec_fwu_trial_boot_cnt() == 0U) {
 				WARN("Trial FWU fails %u times\n",
 				     FWU_MAX_TRIAL_REBOOT);