sandbox: Enable CONFIG_CMD_LZMADEC in sandbox.h

As Simon Glass requested it, here's a patch that enables
CONFIG_CMD_LZMADEC in sandbox.

Signed-off-by: Patrice Bouchand <pbfwdlist@gmail.com>
Signed-off-by: Simon Glass <sjg@chromium.org>

include/configs/sandbox.h

@@ -169,4 +169,6 @@
 
 #define CONFIG_TPM_TIS_SANDBOX
 
+#define CONFIG_CMD_LZMADEC
+
 #endif