libc/eglibc: fix downloading

Since Subversion 1.6.13 was released, it is no longer possible
to checkout/export to the current working directory using '.'
(eg. "svn co bla://blabla/foo/bar ." no longer extracts the content
of bar into ./ but into ./bar).

Fix this by luring Subversion to extract into "$(pwd)", which has
the advantage of working both with all known versions so far.

At the same time, remove the useless redirection.
(transplanted from 42cc9bd0db7ea6d690efab40742881414f7c1277)

 # Dummy config file to not use a C library *at all*

 # depends on BARE_METAL

 config LIBC_none

     help

       Do not use a C library.

       This is usefull if your project is self-contained, does not rely on

       an external C library, and provides all the necessary bits.

       Most probably usefull to bootloaders, as they generally don't depend

       on the C library.

       If unsure: do *not* choose that, and use another option in the choice.