Fix missing mpc
Squashed 'lib/mpc/' content from commit 6af8360

git-subtree-dir: lib/mpc
git-subtree-split: 6af8360517a4d6091fe1580914be72f4d01c82c3
Merge commit '01d5688b1dd93e89d95bdf2db53e9c0d9ce4377f' as 'lib/mpc'
Fixed problems on Linux and when doing initial build