* environ.h, expression.h, frame.h, gdbcmd.h, gdbcore.h,

* environ.h, expression.h, frame.h, gdbcmd.h, gdbcore.h,
inferior.h, language.h, signame.h, target.h, terminal.h,
tm-68k.h, tm-i386v.h, tm-sparc.h, tm-sun386.h, tm-symmetry.h,
xm-i386v.h, xm-sparc.h: Prototypes for all external functions.
Lint.