net/pcap: convert config option to a macro

net/pcap: convert config option to a macro

pcap PMD is using ring PMD configuration parameters to set max number of
queues. This creates an unnecessary dependency and confusion.

Stop using configuration parameter to set max number of queues and
convert this variable into a macro within source code, to simplify
configuration file.

Default value of macro is same as ring parameter's default.

pcap pmd doesn't need to be configured in a detail to set rx and tx max
queue numbers separately, so using same macro for both queues.

Signed-off-by: Ferruh Yigit <ferruh.yigit@intel.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>