util: Avoid possible error in virCommandMassClose
util: Avoid possible error in virCommandMassClose

Avoid the chance that sysconf(_SC_OPEN_MAX) returns -1 and thus
would cause virBitmapNew would attempt to allocate a very large
bitmap.

Found by Coverity

Signed-off-by: John Ferlan <87558058f6f829e5ec976c8ef960720af4ff9c7d@redhat.com>
ACKed-by: Peter Krempa <2cf5c04c61aa466e4a47bfedc747d17279c72ffc@redhat.com>

libvirt/libvirt,libvirt/libvirt,nertpinx/libvirt,andreabolognani/libvirt,olafhering/libvirt,jardasgit/libvirt,jfehlig/libvirt,libvirt/libvirt,fabianfreyer/libvirt,olafhering/libvirt,jardasgit/libvirt,crobinso/libvirt,zippy2/libvirt,andreabolognani/libvirt,jardasgit/libvirt,zippy2/libvirt,zippy2/libvirt,jardasgit/libvirt,libvirt/libvirt,olafhering/libvirt,jfehlig/libvirt,crobinso/libvirt,jfehlig/libvirt,fabianfreyer/libvirt,jfehlig/libvirt,andreabolognani/libvirt,andreabolognani/libvirt,olafhering/libvirt,nertpinx/libvirt,zippy2/libvirt,nertpinx/libvirt,nertpinx/libvirt,nertpinx/libvirt,fabianfreyer/libvirt,jardasgit/libvirt,crobinso/libvirt,crobinso/libvirt,fabianfreyer/libvirt,andreabolognani/libvirt,fabianfreyer/libvirt