tpm: sandbox: Support self-test continue in emulator

Add support for the self-test continue command in the TPM v1.2 emulator,
to match the functionality in the TPM v2 emulator.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/drivers/tpm/tpm_tis_sandbox.c b/drivers/tpm/tpm_tis_sandbox.c
index 2bc7dc8..d734106 100644
--- a/drivers/tpm/tpm_tis_sandbox.c
+++ b/drivers/tpm/tpm_tis_sandbox.c
@@ -221,6 +221,7 @@
 	case 0x72: /* physical set deactivated */
 	case 0x99: /* startup */
 	case 0x50: /* self test full */
+	case 0x53: /* self test continue */
 	case 0x4000000a:  /* assert physical presence */
 		*recv_len = 12;
 		memset(recvbuf, '\0', *recv_len);