compress/qat: fix out-of-bounds write

compress/qat: fix out-of-bounds write

QAT array for sgls in intermediate buffer structure
was #defined to 1, but setup code hardcoded as if 2 buffers
so causing out of bounds write. Reworked to loop correctly
using #define.

Fixes: a124830a6f00 ("compress/qat: enable dynamic huffman encoding")

Reported-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Signed-off-by: Fiona Trahe <fiona.trahe@intel.com>
Tested-by: Jerin Jacob <jerin.jacob@caviumnetworks.com>
Acked-by: Bruce Richardson <bruce.richardson@intel.com>
Acked-by: Tomasz Jozwiak <tomaszx.jozwiak@intel.com>