manual/configure.txt: reword part about internal toolchain backend

Signed-off-by: Jerzy Grzegorek <jerzy.grzegorek@trzebnica.net>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>

docs/manual/configure.txt

@@ -100,7 +100,7 @@ most important ones allow to:
    toolchain should have largefile support (i.e support for files
    larger than 2 GB on 32 bits systems), IPv6 support, RPC support
    (used mainly for NFS), wide-char support, locale support (for
-   internationalization), C++ support, thread support. Depending on
+   internationalization), C++ support or thread support. Depending on
    which options you choose, the number of userspace applications and
    libraries visible in Buildroot menus will change: many applications
    and libraries require certain toolchain options to be enabled. Most