contrib/build-push-ceph-container-imgs.sh: Fixing current ARCH
contrib/build-push-ceph-container-imgs.sh: Fixing current ARCH

When the arm64 build makes the call, the x86_64 is hardcoded and make it fails.
So let's use the default host arch instead.

Signed-off-by: Erwan Velu <dbf153a4f846e5c13692f4d75719ee25e7660abd@redhat.com>

JrCs/ceph-docker,ceph/ceph-docker,JrCs/ceph-docker,JrCs/ceph-docker,ceph/ceph-docker