Fixes [YOCTO #10069]
Added a note at the end of the variable description to
explain how runtime virual dependencies work.
(From yocto-docs rev: de1d16017c27b6b2502735fc41acd22660f6e7b9)
Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>