doc: removed extra explanation in api/buffer.md

PR-URL: #17796
Reviewed-By: Anatoli Papirovski <apapirovski@mac.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Jon Moss <me@jonathanmoss.me>
Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>

Author: WaleedAshraf

doc/api/buffer.md

@@ -1047,13 +1047,11 @@ changes:
 * `targetStart` {integer} The offset within `target` at which to begin
   comparison. **Default:** `0`
 * `targetEnd` {integer} The offset with `target` at which to end comparison
-  (not inclusive). Ignored when `targetStart` is `undefined`.
-  **Default:** `target.length`
+  (not inclusive). **Default:** `target.length`
 * `sourceStart` {integer} The offset within `buf` at which to begin comparison.
-  Ignored when `targetStart` is `undefined`. **Default:** `0`
+  **Default:** `0`
 * `sourceEnd` {integer} The offset within `buf` at which to end comparison
-  (not inclusive). Ignored when `targetStart` is `undefined`.
-  **Default:** [`buf.length`]
+  (not inclusive). **Default:** [`buf.length`]
 * Returns: {integer}
 
 Compares `buf` with `target` and returns a number indicating whether `buf`
@@ -1123,9 +1121,9 @@ added: v0.1.90
 * `targetStart` {integer} The offset within `target` at which to begin
   copying to. **Default:** `0`
 * `sourceStart` {integer} The offset within `buf` at which to begin copying from.
-  Ignored when `targetStart` is `undefined`. **Default:** `0`
+  **Default:** `0`
 * `sourceEnd` {integer} The offset within `buf` at which to stop copying (not
-  inclusive). Ignored when `sourceStart` is `undefined`. **Default:** [`buf.length`]
+  inclusive). **Default:** [`buf.length`]
 * Returns: {integer} The number of bytes copied.
 
 Copies data from a region of `buf` to a region in `target` even if the `target`