Add SDK marker to file names of existing pre-compiled packages (copies)

[rwaldron]

This doesn't require any changes to the repo, but is related to #45

I plan to make copies of the existing packages and add "uclibc" to the name, eg:

xpc-connection-0.1.4-Release-node-v48-linux-mipsel-uclibc.tgz

Making a copy will ensure the older CLI and firmware will continue working as expected.