Clean raft/neighbors comments (rapidsai#1651)

Clean up unused/outdated `raft/neighbors` comments

Authors:
  - Anupam (https://github.com/aamijar)

Approvers:
  - Divye Gala (https://github.com/divyegala)

URL: rapidsai#1651

Author: aamijar

cpp/bench/ann/src/cuvs/cuvs_cagra_wrapper.h

@@ -22,8 +22,6 @@
 #include <raft/core/logger.hpp>
 #include <raft/core/operators.hpp>
 #include <raft/linalg/unary_op.cuh>
-// #include <raft/neighbors/dataset.hpp>
-// #include <raft/neighbors/detail/cagra/cagra_build.cuh>
 #include <raft/util/cudart_utils.hpp>
 
 #include <rmm/device_uvector.hpp>

docs/source/c_api/neighbors_bruteforce_c.rst

@@ -7,7 +7,7 @@ The bruteforce method is running the KNN algorithm. It performs an extensive sea
    :language: c
    :class: highlight
 
-``#include <raft/neighbors/bruteforce.h>``
+``#include <cuvs/neighbors/bruteforce.h>``
 
 Index
 -----

docs/source/c_api/neighbors_cagra_c.rst

@@ -8,7 +8,7 @@ CAGRA is a graph-based nearest neighbors algorithm that was built from the groun
    :language: c
    :class: highlight
 
-``#include <raft/neighbors/cagra.h>``
+``#include <cuvs/neighbors/cagra.h>``
 
 Index build parameters
 ----------------------

docs/source/c_api/neighbors_hnsw_c.rst

@@ -8,7 +8,7 @@ This is a wrapper for hnswlib, to load a CAGRA index as an immutable HNSW index.
    :language: c
    :class: highlight
 
-``#include <raft/neighbors/hnsw.h>``
+``#include <cuvs/neighbors/hnsw.h>``
 
 Index search parameters
 -----------------------

docs/source/c_api/neighbors_ivf_flat_c.rst

@@ -7,7 +7,7 @@ The IVF-Flat method is an ANN algorithm. It uses an inverted file index (IVF) wi
    :language: c
    :class: highlight
 
-``#include <raft/neighbors/ivf_flat.h>``
+``#include <cuvs/neighbors/ivf_flat.h>``
 
 Index build parameters
 ----------------------

docs/source/c_api/neighbors_ivf_pq_c.rst

@@ -7,7 +7,7 @@ The IVF-PQ method is an ANN algorithm. Like IVF-Flat, IVF-PQ splits the points i
    :language: c
    :class: highlight
 
-``#include <raft/neighbors/ivf_pq.h>``
+``#include <cuvs/neighbors/ivf_pq.h>``
 
 Index build parameters
 ----------------------

docs/source/c_api/neighbors_vamana_c.rst

@@ -8,7 +8,7 @@ Vamana is the graph construction algorithm behind the well-known DiskANN vector
    :language: c
    :class: highlight
 
-``#include <raft/neighbors/vamana.h>``
+``#include <cuvs/neighbors/vamana.h>``
 
 Index build parameters
 ----------------------