Just like -lpthread was passed in LIBS, -latomic should also be passed
in LIBS. In order for this to work, we however need to first fix
cc-tool's Makefile.am so that it does not overwrite LIBS.
This is the first part of fixing the build of cc-tool in a static
linking scenario on SPARC, i.e to fix:
http://autobuild.buildroot.net/results/ed9f2524d0ccef318ff1bc99e5dea980111de989/
The patch has been merged upstream, in
553f9c6016.
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>