jack2: add .hash file
Fixes:
http://autobuild.buildroot.org/results/cc3/cc3590d9c602b38701398786741fceb612445b92/
http://autobuild.buildroot.org/results/2a6/2a691d01d8c91aa1058960f5176ad611b3549f36/
Similar to jquery-keyboard, it seems the jack2 tarball on the autobuilder
is corrupt. Fix it by adding a .hash file so it falls back to our s.b.o
mirror.
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>
Peter Korsgaard