doc: avoid referring to C array size

The size of arrays is measured in bytes in C, not in the number of
elements. The napi_get_cb_info function takes the length of the
array, that is, the number of elements it can contain, and not its size.

PR-URL: #35300
Reviewed-By: Anna Henningsen <[email protected]>
Reviewed-By: Michael Dawson <[email protected]>
Reviewed-By: Colin Ihrig <[email protected]>
Reviewed-By: Jiawen Geng <[email protected]>
Reviewed-By: Chengzhong Wu <[email protected]>
Reviewed-By: Gabriel Schulhof <[email protected]>

doc/api/n-api.md

@@ -4388,8 +4388,8 @@ napi_status napi_get_cb_info(napi_env env,
 
 * `[in] env`: The environment that the API is invoked under.
 * `[in] cbinfo`: The callback info passed into the callback function.
-* `[in-out] argc`: Specifies the size of the provided `argv` array and receives
-  the actual count of arguments.
+* `[in-out] argc`: Specifies the length of the provided `argv` array and
+  receives the actual count of arguments.
 * `[out] argv`: Buffer to which the `napi_value` representing the arguments are
   copied. If there are more arguments than the provided count, only the
   requested number of arguments are copied. If there are fewer arguments