re PR driver/57651 (gcc-ar and gcc-nm don't find the lto plugin)

2013-06-19  Matthias Klose  <doko@ubuntu.com>

        PR driver/57651
        * file-find.h (find_a_file): Add a mode parameter.
        * file-find.c (find_a_file): Likewise.
        * gcc-ar.c (main): Call find_a_file with R_OK for the plugin,
        with X_OK for the executables.
        * collect2.c (main): Call find_a_file with X_OK.

From-SVN: r200219