Fix test for activate_credential.

Author: dgarske

examples/attestation/activate_credential.c

@@ -67,7 +67,7 @@ int TPM2_ActivateCredential_Example(void* userCtx, int argc, char *argv[])
     int dataSize = 0;
 #endif
     const char *input = "cred.blob";
-    const char *keyblob = "keyblob.bin";
+    const char *keyblob = "ek.bin";
 
     ActivateCredential_In  activCredIn;
     ActivateCredential_Out activCredOut;