[Ada] Update reference with description of type resolution

[Pierre-Marie de Rodat]

A reference in the comment about the type resolution described in
Sem_Ch4 refers to description with a header "Handling of Overload
Resolution", but this has been moved to Sem_Type.

Tested on x86_64-pc-linux-gnu, committed on trunk

gcc/ada/

        * sem_res.ads: Update reference in comment.
        * sem_type.ads: Fix casing in a name of a unit.
diff --git a/gcc/ada/sem_res.ads b/gcc/ada/sem_res.ads
--- a/gcc/ada/sem_res.ads
+++ b/gcc/ada/sem_res.ads
@@ -31,7 +31,7 @@ with Types; use Types;
 
 package Sem_Res is
 
-   --  As described in Sem_Ch4, the type resolution proceeds in two phases.
+   --  As described in Sem_Type, the type resolution proceeds in two phases.
    --  The first phase is a bottom up pass that is achieved during the
    --  recursive traversal performed by the Analyze procedures. This phase
    --  determines unambiguous types, and collects sets of possible types


diff --git a/gcc/ada/sem_type.ads b/gcc/ada/sem_type.ads
--- a/gcc/ada/sem_type.ads
+++ b/gcc/ada/sem_type.ads
@@ -85,7 +85,7 @@ package Sem_Type is
    --  with the appropriate use clause. The global variable Candidate_Type is
    --  set in Add_One_Interp whenever an interpretation might be legal for an
    --  operator if the type were directly visible. This variable is used in
-   --  sem_ch4 when no legal interpretation is found.
+   --  Sem_Ch4 when no legal interpretation is found.
 
    Candidate_Type : Entity_Id;