Remove weirdnesses caused by 'letrec*' behavior of record field initializers.

* gnu/packages/bootstrap.scm (package-from-tarball): Remove '*' from
  parameter names.  Adjust accordingly.
* gnu/packages/linux-initrd.scm (expression->initrd): Use 'name'
  directly, removing the 'name*' alias.
* gnu/packages/linux.scm (linux-libre-headers, linux-libre): Rename
  'version*' to 'version'.