error: 'CHAR_BIT' undeclared. fix compile failure with musl libc

[alexminder]

src/libcrun/cgroup-systemd.c: In function 'cpuset_string_to_bitmask':
src/libcrun/cgroup-systemd.c:84:49: error: 'CHAR_BIT' undeclared (first use in this function)
   84 |       if (end_range >= (long long) (mask_size * CHAR_BIT))
      |                                                 ^~~~~~~~
src/libcrun/cgroup-systemd.c:39:1: note: 'CHAR_BIT' is defined in header '<limits.h>'; did you forget to '#include <limits.h>'?
   38 | #  include <systemd/sd-bus.h>
  +++ |+#include <limits.h>
   39 |
src/libcrun/cgroup-systemd.c:84:49: note: each undeclared identifier is reported only once for each function it appears in
   84 |       if (end_range >= (long long) (mask_size * CHAR_BIT))
      |                                                 ^~~~~~~~
make[2]: *** [Makefile:1812: src/libcrun/libcrun_testing_a-cgroup-systemd.o] Error 1
make[2]: *** Waiting for unfinished jobs....
make[2]: Leaving directory '/var/tmp/portage/app-containers/crun-1.14.3/work/crun-1.14.3'
make[1]: *** [Makefile:2801: all-recursive] Error 1
make[1]: Leaving directory '/var/tmp/portage/app-containers/crun-1.14.3/work/crun-1.14.3'
make: *** [Makefile:1046: all] Error 2

[packit-as-a-service]

Ephemeral COPR build failed. @containers/packit-build please check.

[giuseppe]

the DCO test is failing because the commit misses the "Signed-off-by" line. Please amend it to your patch, as documented here: https://github.com/containers/crun/blob/main/CONTRIBUTING.md#submitting-a-patch

[rhatdan]

@alexminder Are you still working on this?