Explain that reducing its value to reduce system load
is not sufficient if PARALLEL_MAKE is not reduced as well.
(From yocto-docs rev: f4986faa5576ec1c146e606220421a686c4a9b57)
Signed-off-by: Michael Opdenacker <michael.opdenacker@bootlin.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>