* rs6000/sysv4.h (CPP_OS_LINUX_SPEC): Fix conditions

        for -Dunix and -Dlinux, and remove duplicate definition.
        Change -Asystem(linux) to -Asystem(posix).
        (CPP_OS_SOLARIS_SPEC): Fix conditions for -Dunix, -Dsun,
        -DSVR4, -D__EXTENSIONS__.
        * rs6000/linux.h (CPP_PREDEFINES): Remove -Dunix,
        -Dlinux, -Asystem(linux), and -Asystem(unix).


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@26329 138bc75d-0d04-0410-961f-82ee72b054a4