compile: set debug compile: Display GCC driver filename

compile: set debug compile: Display GCC driver filename

gdb/ChangeLog
2015-05-24  Jan Kratochvil  <jan.kratochvil@redhat.com>

    * compile/compile.c (compile_to_object): Conditionally call set_verbose.
    Conditionally call compile or compile_v0.

include/ChangeLog
2015-05-24  Jan Kratochvil  <jan.kratochvil@redhat.com>

    * gcc-interface.h (enum gcc_base_api_version): Add GCC_FE_VERSION_1.
    (struct gcc_base_vtable): Rename compile to compile_v0.  Update comment
    for compile.  New methods set_verbose and compile.