complibs: disable building shared libs

Managing the shared version of the companion libraries
has become cumbersome.

Also, it will one day be possible to use the companion
libraries from the host distribution, and then we will
be able to easily use either shared or static libs.

As a side note, while working on the canadian-rework
series, it has become quite more complex to properly
handle shared companion libraries, as they need to be
built both for the build and gost systems. That's not
easy to handle. At all.

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

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.