net/ionic: enable meson build
net/ionic: enable meson build

Otherwise the ionic PMD is never built.

Signed-off-by: Andrew Boyer <a60237c2e400ae1b26d0ba5ac500b80b58b52b9a@pensando.io>
Reviewed-by: Ferruh Yigit <ba8734c3c506d2e3557bd4ac8fdaccd25bdb9aa7@intel.com>

john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk,john-mcnamara-intel/dpdk