Variable was incorrect in the manual.
(From yocto-docs rev: d1ddb06cdcec48ab64df3a03f3ef845da0b13c80)
Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Scott Rifenbark <scott.m.rifenbark@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>