Doing both os.unsetenv(foo) and then del os.environ[foo] is pointless as del
will call unsetenv automatically.
(Bitbake rev: a4463e2ff3c7d234320176d671719243292f1af0)
Signed-off-by: Ross Burton <ross.burton@intel.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>