small libf2c cleanups

[Dave Love]

>>>>> "Jeffrey" == Jeffrey A Law <law@cygnus.com> writes:

 >> * libF77/signal_.c (G77_signal_0): Make return type sig_pf as well.

Note that changes to return types of the intrinsic implementations
should be reflected (at least) in com-rt.def.

 >> * libI77/fio.h: Include <string.h> if STDC_HEADERS.

Is this actually necessary?

 >> * libU77/chmod_.c: Likewise.

I wonder how it got like that...

 Jeffrey> Installed.  We'll have to keep an eye on the signal stuff --
 Jeffrey> I'm not 100% sure of what we want to do with it either.

I realize that the libf2c implemenation has changed underneath
configure and I either failed to notice or forgot to sort it out.
I'll investigate.

BTW I don't think burley is reading the list, primarily in view of his
mail normally being delivered to the GNU system...