doc: remove web references to internal guides

doc: remove web references to internal guides

The guides should be referenced locally with RST syntax
:doc: (beginning of page) or :ref: (specific chapter).
The links to doc.dpdk.org/guides/ are removed.

The links to the doc.dpdk.org/api/ are acceptable,
but should not point to a specific version, so one is fixed.

Signed-off-by: Thomas Monjalon <thomas@monjalon.net>
Acked-by: Ajit Khaparde <ajit.khaparde@broadcom.com>
Acked-by: David Marchand <david.marchand@redhat.com>