doc: convert prog guide glossary to definition list
doc: convert prog guide glossary to definition list

Converted the Glossary table in the Programmer's Guide
to a definition list to improve rendering.

Signed-off-by: John McNamara <af31595c36a4239b9676e9b3a777d3e2f15a6c4d@intel.com>

phermansson/dpdk,phermansson/dpdk,phermansson/dpdk,phermansson/dpdk