[PATCH] BLOCK: Revert patch to hack around undeclared sigset_t in linux/compat.h

Revert Andrew Morton's patch to temporarily hack around the lack of a
declaration of sigset_t in linux/compat.h to make the block-disablement
patches build on IA64.  This got accidentally pushed to Linus and should
be fixed in a different manner.

Also make linux/compat.h #include asm/signal.h to gain a definition of
sigset_t so that it can externally declare sigset_from_compat().

This has been compile-tested for i386, x86_64, ia64, mips, mips64, frv, ppc and
ppc64 and run-tested on frv.

Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

arch/mips/kernel/signal_n32.c

@@ -42,8 +42,6 @@
 
 #include "signal-common.h"
 
-extern void sigset_from_compat(sigset_t *set, compat_sigset_t *compat);
-
 /*
  * Including <asm/unistd.h> would give use the 64-bit syscall numbers ...
  */
@@ -83,6 +81,8 @@ struct rt_sigframe_n32 {
 #endif
 };
 
+extern void sigset_from_compat (sigset_t *set, compat_sigset_t *compat);
+
 save_static_function(sysn32_rt_sigsuspend);
 __attribute_used__ noinline static int
 _sysn32_rt_sigsuspend(nabi_no_regargs struct pt_regs regs)