bad change to process.c

[Dave Love]

This change breaks compilation under Irix 6.5.19, at least.  I suggest
reverting the major part of it.

2003-05-25  Stefan Monnier  <address@hidden>

        * process.c (allocate_pty): Remove `unused var stb' and
        `cp might be used uninitialized' warnings.

cc -D_LANGUAGE_C -c  -Demacs -DHAVE_CONFIG_H -DUSE_LUCID  -I. 
-I/home/fx/esrc/src        -g3 -O -OPT:Olimit=3500  /home/fx/esrc/src/process.c
cc-1020 cc: ERROR File = /home/fx/esrc/src/process.c, Line = 479
  The identifier "stb" is undefined.

        PTY_OPEN;
        ^


[The greatest service to eliminating warnings would be fixing the
unsigned char v. char issue mentioned in TODO...]