[PATCH] examples/l2fwd-cat: fix external build

[Thomas Monjalon]

22/06/2023 15:48, Thomas Monjalon:
> From: David Marchand <david.marchand at redhat.com>
> 
> cpu_set_t definition requires _GNU_SOURCE.
> 
> Fixes: e0473c6d5b18 ("eal: fix build with musl")
> Cc: stable at dpdk.org
> 
> Signed-off-by: David Marchand <david.marchand at redhat.com>
> ---
> This patch was missing in the patchset to make all examples compile.
> It will be merged with others from:
> 	"Test examples compilation externally"

Tested-by: Thomas Monjalon <thomas at monjalon.net>
and applied.