devtools: fix debug build test

When testing build with +debug options, the statistics are enabled.
It was wrongly matching CONFIG_RTE_IBVERBS_LINK_STATIC.
The pattern is fixed to match only statistics config options.

Fixes: 2c0dd7b69fb0 ("config: add static linkage of mlx dependency")
Cc: stable@dpdk.org
Reported-by: Ali Alnubani <alialnu@mellanox.com>
Signed-off-by: Thomas Monjalon <thomas@monjalon.net>