um: kill system-um.h

most of it belonged in irqflags.h, actually

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
diff --git a/arch/um/include/asm/irqflags.h b/arch/um/include/asm/irqflags.h
index 659b9ab..c780d8a 100644
--- a/arch/um/include/asm/irqflags.h
+++ b/arch/um/include/asm/irqflags.h
@@ -1,6 +1,42 @@
 #ifndef __UM_IRQFLAGS_H
 #define __UM_IRQFLAGS_H
 
-/* Empty for now */
+extern int get_signals(void);
+extern int set_signals(int enable);
+extern void block_signals(void);
+extern void unblock_signals(void);
+
+static inline unsigned long arch_local_save_flags(void)
+{
+	return get_signals();
+}
+
+static inline void arch_local_irq_restore(unsigned long flags)
+{
+	set_signals(flags);
+}
+
+static inline void arch_local_irq_enable(void)
+{
+	unblock_signals();
+}
+
+static inline void arch_local_irq_disable(void)
+{
+	block_signals();
+}
+
+static inline unsigned long arch_local_irq_save(void)
+{
+	unsigned long flags;
+	flags = arch_local_save_flags();
+	arch_local_irq_disable();
+	return flags;
+}
+
+static inline bool arch_irqs_disabled(void)
+{
+	return arch_local_save_flags() == 0;
+}
 
 #endif