don't write to a constant pointer

instead allocate action on the stack and copy the data there
Update MacOS_X_Challenge-Response.adoc
Update MacOS_X_Challenge-Response.adoc
Update MacOS_X_Challenge-Response.adoc
Update MacOS_X_Challenge-Response.adoc
Update MacOS_X_Challenge-Response.adoc
Update YubiKey_and_FreeRADIUS_via_PAM.adoc
Update YubiKey_and_FreeRADIUS_via_PAM.adoc
Update and rename Yubikey_and_SELinux_on_Fedora_18_and_up.txt to Yubikey_and_SELinux_on_Fedora_18_and_up.adoc
Update Two_Factor_PAM_Configuration.adoc
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