On Linux x86_64, kmem cache can have size up to 4M,
however increasing spl_kmem_cache_slab_limit can lead
to crash due to the size check inconsistency.
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Youzhong Yang <yyang@mathworks.com>
Closes#15757