jack2: Add dependency on atomic intrinsics

Jack requires GCC built-in atomic functions which are architecture specific
and may not be implemented.

This fixes:
http://autobuild.buildroot.net/results/c218be876d3abf7a8e212b6d526595bfd835e1c5/



Signed-off-by: Anton Kolesov <Anton.Kolesov@synopsys.com>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>