package.bbclass: Replace undefined 'src' with valid variable

After rewrite of split_and_strip_files src var is no longer
available here where it is used so we should replace it with
a valid value

Signed-off-by: Khem Raj <raj.khem@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>
bitbake.conf: Update hashconfig after BB_ORIGENV changes

We should ignore BB_ORIGENV from the hash for the config data. There
are also a number of variables which no longer make it into the data
store so we can drop these from the hash whitelist.

Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>