fix(tpm): extend timeout before reading data

- extended timeout before reading data from timeout_msec_c (200ms) to timeout_msec_a (750ms)
- new timeout is compatible with spec and avoids incorrect behavior

Change-Id: I35a44e93a331a11fcab32b3b64c2adf770e5951d
Signed-off-by: Jenna May <jenna.may@arm.com>
diff --git a/drivers/tpm/tpm2_fifo.c b/drivers/tpm/tpm2_fifo.c
index 7c4b9d8..07a0bc0 100644
--- a/drivers/tpm/tpm2_fifo.c
+++ b/drivers/tpm/tpm2_fifo.c
@@ -246,7 +246,7 @@
 
 	err = tpm2_wait_reg_bits(tpm_base_addr + TPM_FIFO_REG_STATUS,
 				TPM_STAT_AVAIL,
-				chip_data->timeout_msec_c,
+				chip_data->timeout_msec_a,
 				status);
 	if (err < 0) {
 		return err;