Ensure we do not erroneously split on + in RDEPENDS/RRECOMMENDS e.g.
libstdc++-dev was being split into libstdc and -dev.
(From OE-Core rev: cad533880df42ad4fe6f04d56d3a59cb4a033275)
Signed-off-by: Paul Eggleton <paul.eggleton@linux.intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>