* t-freebsd (USER_H): Include EXTRA_HEADERS and LANG_EXTRA_HEADERS.
        * x-netbsd: Likewise
        * x-dgux (USER_H): Include EXTRA_HEADERS and LANG_EXTRA_HEADERS
        (INSTALL_HEADERS): Delete.
        * x-dguxbcs: Likewise.
        * x-hp3bsd44: Likewise
        * x-pa: Likewise.

From-SVN: r14959