tpm: Fix memory leak and use existing variable instead

Use the existing variables rather then calling virTPMSwtpmXYZ().
Signed-off-by: NStefan Berger <stefanb@linux.ibm.com>
Reviewed-by: NJohn Ferlan <jferlan@redhat.com>
Message-Id: <20190726205633.2041912-2-stefanb@linux.vnet.ibm.com>

src/qemu/qemu_tpm.c

@@ -512,7 +512,7 @@ qemuTPMEmulatorRunSetup(const char *storagepath,
                 VIR_TPM_SWTPM_SETUP_FEATURE_CMDARG_PWDFILE_FD)) {
             virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED,
                 _("%s does not support passing a passphrase using a file "
-                  "descriptor"), virTPMGetSwtpmSetup());
+                  "descriptor"), swtpm_setup);
             goto cleanup;
         }
         if ((pwdfile_fd = qemuTPMSetupEncryption(secretuuid, cmd)) < 0)
@@ -652,7 +652,7 @@ qemuTPMEmulatorBuildCommand(virDomainTPMDefPtr tpm,
         if (!virTPMSwtpmCapsGet(VIR_TPM_SWTPM_FEATURE_CMDARG_PWD_FD)) {
             virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED,
                   _("%s does not support passing passphrase via file descriptor"),
-                  virTPMGetSwtpm());
+                  swtpm);
             goto error;
         }