Rename VOID into void

[magv]

Hi, all. I'd like to suggest a few minor style changes, and if you'll approve them, I'll send patches.

My proposal: rename VOID back into void.

If you'll look at form3.h, half of the function declarations are already void, and as a general rule, I would like to see more standard types being used when possible. void is certainly a standard type that does not need a typedef.

Approve or disapprove?

[tueda]

In my opinion, using void (instead of VOID) makes sense. Support for K&R was removed many years ago in 77d49bb.

[magv]

Here's the patch: #662.