Reformat .h files.

I did my best to exempt some of the bigger aligned blocks from the reformatting
using the /* clang-format off */ and /* clang-format on */ tags. Probably some
that shouldn't have been formatted were anyway; if you encounter them, please
fix.

The clang-format tags were left in on the basis that it's much easier to prune
those out later than to put them back in, and it means that, modulo my custom
version of clang-format, I should be able to run clang-format on the source tree
again without changing anything, now that Pat has fixed the VA_DECL issues.

win/gnome/gn_xpms.h

@@ -4,7 +4,7 @@
 /* Copyright (C) 1998 by Erik Andersen <andersee@debian.org> */
 /* NetHack may be freely redistributed.  See license for details. */
 /* These XPMs are the artwork of Warwick Allison
- * <warwick@troll.no>.  They have been borrowed from 
+ * <warwick@troll.no>.  They have been borrowed from
  * the most excellent NetHackQt, until such time as
  * we can come up with something better.
  *
@@ -12,6 +12,7 @@
  * http://www.troll.no/~warwick/nethack/
  */
 
+/* clang-format off */
 /* XPM */
 static char *blind_xpm[] = {
 /* width height ncolors chars_per_pixel */
@@ -1449,4 +1450,4 @@ static char *nothing_xpm[] = {
 "oooooooooooooooooooooooooooooooooooooooo",
 "oooooooooooooooooooooooooooooooooooooooo"
 };
-
+/* clang-format on */