Patch: fix #line directives in bison output

[Joel Brobecker]

Hi Tom,

I'll admit being lazy this evening and not having the energy trying to
understand the incantations being used in the makefile, and why we have
to make the following targets non-.PRECIOUS.  Something did catch my eye, 
though:

> -.PRECIOUS: ada-exp.c ada-lex.c
> -.PRECIOUS: c-exp.c
> -.PRECIOUS: f-exp.c
> -.PRECIOUS: jv-exp.c
> -.PRECIOUS: m2-exp.c
> -.PRECIOUS: objc-exp.c
> -.PRECIOUS: p-exp.c
> +.PRECIOUS: ada-exp.c

Did you mean the last line to be "ada-lex.c"?

-- 
Joel