Bug fix in qat_compress.c for vmalloc addr check

Remove the unused vmalloc address check, and function mem_to_page
will handle the non-vmalloc address when map it to a physical
address.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Weigang Li <weigang.li@intel.com>
Closes #7125