complibs: fixup the host complibs install dir

It's easier to have as much as possible stuff in the same place to
ease backup/restore, and make things easier to follow.

Move the host companion libraries install dir as a sub-dir of the
build-tools install dir (but not directly in it, it would break
for canadian or cross-native).

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

# Bare metal config options

## select BARE_METAL

##

## help 'Bare metal' refers to those programs that run without any kernel.

## help

## help You probably want to say 'y' here if you plan to use your compiler

## help to build bootloaders. It is not yet suitable to build Linux kernels,

## help though, because the APCI stuff relies on the target C library headers

## help being available?!?!...