Documentation/virt/kvm/api.rst: Add protvirt dump/info api descriptions

Time to add the dump API changes to the api documentation file.
Also some minor cleanup.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
Acked-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Link: https://lore.kernel.org/r/20220517163629.3443-11-frankja@linux.ibm.com


Message-Id: <20220517163629.3443-11-frankja@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@linux.ibm.com>