[Ada] improve misspelling handling

[Arnaud Charlet <charlet at adacore dot com>]

Tested on i686-linux, committed on trunk.

With this additional patch in place, here is the output from
compiling the test p2.adb with switch -gnatq

Compiling: p2.adb (source file time stamp: 2006-10-31 11:33:22)

     1.
     2. package body P2 is
     3.
     4.    procedure Init is
     5.    begin
     6.       0utputs := 0;
              |
        >>> identifier may not start with digit
        >>> "0utputs" is undefined
        >>> possible misspelling of "Outputs"

     7.    end Init;
     8.
     9. end P2;

Compiling: p2.ads (source file time stamp: 2006-10-31 11:33:22)

     1. package P2
     2. --# own Outputs;
     3. is
     4.    Outputs : Integer;
     5.
     6.    procedure Init;
     7.    --# global out Outputs;
     8.    --# derives Outputs from ;
     9. end P2;

2006-10-31  Robert Dewar  <dewar@adacore.com>

	* g-speche.ads, g-speche.adb: Add special case to recognize misspelling
	initial letter o as a zero.

Attachment: difs
Description: Text document