remove config prefix used with make

remove config prefix used with make

The config options CONFIG_RTE_* are simple RTE_* defines with meson.
Now that make support is dropped, update the names in logs and comments.

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Acked-by: Ruifeng Wang <ruifeng.wang@arm.com>
Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Acked-by: Haiyue Wang <haiyue.wang@intel.com>
Acked-by: Andrew Rybchenko <andrew.rybchenko@oktetlabs.ru>
Acked-by: David Marchand <david.marchand@redhat.com>