Do not cast unused return values to void

A small style fix that removes all remaining "(void)" casts. Using these
isn't encouraged in GNU coding guidelines and doesn't serve a certain
purpose, except for satisfying a few static code analysis tools. We
already nuked some of these in previous patches, but this semantic patch
should fix what's left:

    @@
    identifier func;
    @@

    - (void)func (
    + func (
    ...);

Long lines were re-formatted manually.

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

src/sigs.c

@@ -61,7 +61,7 @@ generic_hdlr (int sig)
     case SIGWINCH:
       resize = 1;
       clearok (curscr, TRUE);
-      (void)ungetch (KEY_RESIZE);
+      ungetch (KEY_RESIZE);
       break;
     case SIGTERM:
       if (unlink (path_cpid) != 0)