Enable metacopy for overlay driver
Enable metacopy for overlay driver

Is only enabled if the kernel supports the feature. Metacopy was added
in kernel 4.19.

Signed-off-by: Taylor Silva <33b075afcd0610c62dcb82fe76b4c1adc69221da@pivotal.io>
Co-authored-by: Muntasir Chowdhury <3af480f42ae632f8ec7bb4ce9ac5df283cd495d6@pivotal.io>

concourse/baggageclaim,concourse/baggageclaim