libc/eglibc: Add option that allows for getting svn over http://

Instead of getting eglibc over standard svn://svn.eglibc.org
Add an option that allows the user to get source from
http://www.eglibc.org/svn

This is useful if you are behind a firewall or proxy.
If you are behind a proxy, don't forget to configure
${HOME}/.subversion/servers

In the [global] section setup your proxy configuration.

Signed-off-by: Bryan Hundven <bryanhundven@gmail.com>
[yann.morin.1998@anciens.enib.fr: removed useless 'default n']
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

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

 ## depends on BARE_METAL

 ##

 ## help Do not use a C library.

 ## help

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

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

 ## help

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

 ## help on the C library.

 ## help

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