Improve documentation.

Author: godunko

source/ada/lsp-ada_documentation.ads

@@ -37,7 +37,8 @@ package LSP.Ada_Documentation is
    --  Get all the information needed to produce tooltips (hover and completion
    --  requests) for the given declaration.
    --
-   --  @param Name  Defining name's node.
+   --  @param Name    Defining name's node.
+   --  @param Origin  AST node at the origin.
    --  @param Style
    --    Is used by GNATdoc for extracting the associated comments.
    --  @param Qualifier_Text

source/ada/lsp-ada_job_contexts.ads

@@ -161,6 +161,8 @@ package LSP.Ada_Job_Contexts is
       Position : LSP.Structures.TextDocumentPositionParams'Class;
       Name     : out Libadalang.Analysis.Defining_Name;
       Origin   : out Libadalang.Analysis.Ada_Node);
+   --  Return the defining name (canonical part) of the entity and AST node at
+   --  the given location. If an error happened then return No_Defining_Name.
 
    function To_LSP_Location
      (Self   : in out Ada_Job_Context;