tpm: compile Sandbox driver by default

When Sandbox and the TPM stack are both selected, compile Sandbox TPM
driver by default.

Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com>
Reviewed-by: Simon Glass <sjg@chromium.org>
diff --git a/drivers/tpm/Kconfig b/drivers/tpm/Kconfig
index 93264dd..5e3fb32 100644
--- a/drivers/tpm/Kconfig
+++ b/drivers/tpm/Kconfig
@@ -20,6 +20,7 @@
 config TPM_TIS_SANDBOX
 	bool "Enable sandbox TPM driver"
 	depends on TPM_V1 && SANDBOX
+	default y
 	help
 	  This driver emulates a TPMv1.x, providing access to base functions
 	  such as reading and writing TPM private data. This is enough to
@@ -132,6 +133,7 @@
 config TPM2_TIS_SANDBOX
 	bool "Enable sandbox TPMv2.x driver"
 	depends on TPM_V2 && SANDBOX
+	default y
 	select TPM_DRIVER_SELECTED
 	help
 	  This driver emulates a TPMv2.x, providing access to base functions