Canary CI failing to build runc: `Makefile:19: *** Recursive variable 'BUILDTAGS' references itself (eventually). Stop.`

[AkihiroSuda]

https://github.com/containerd/nerdctl/actions/runs/23940088567/job/69825056418

 > [build-runc 4/4] RUN set -x ; GO=xx-go CC=$(xx-info)-gcc STRIP=$(xx-info)-strip make BUILDTAGS="$(grep -oP "^BUILDTAGS := K.*" Makefile  | sed -e s/libpathrs//)" static &&   xx-verify --static runc && cp -v -a runc /out/runc.amd64:
0.334 + sed -e s/libpathrs//
0.343 + grep -oP ^BUILDTAGS := \K.* Makefile
0.361 + xx-info
0.363 + xx-info
0.366 + GO=xx-go CC=x86_64-linux-gnu-gcc STRIP=x86_64-linux-gnu-strip make BUILDTAGS=seccomp urfave_cli_no_docs 
0.366 $(filter-out $(BUILDTAGS_REMOVE),$(BUILDTAGS)) $(BUILDTAGS_ADD) static
0.379 Makefile:19: *** Recursive variable 'BUILDTAGS' references itself (eventually).  Stop.

Makefile variables were changed in runc v1.5.0-rc.2

• Makefile: add RUNC_BUILDTAGS, deprecate EXTRA_BUILDTAGS opencontainers/runc#5171