Remove unused code

None of the returned values is actually used after this procedure call, so
remove it.

Change-Id: I992447ac2173d4d22cf0f8191c67998b5a83eb74
TN: V914-024

Author: Jugst3r

tools/gnatcov/instrument-c.adb

@@ -581,9 +581,6 @@ package body Instrument.C is
          return;
       end if;
 
-      Get_Expansion_Location
-        (Loc, File'Address, Line'Access, Column'Access, Offset'Access);
-
       Info.Actual_Source_Range := (From, To);
 
       --  Check if this is comes from a macro expansion, in which case we need