sparc, sparc64: use arch/sparc/include

The majority of this patch was created by the following script:

***
ASM=arch/sparc/include/asm
mkdir -p $ASM
git mv include/asm-sparc64/ftrace.h $ASM
git rm include/asm-sparc64/*
git mv include/asm-sparc/* $ASM
sed -ie 's/asm-sparc64/asm/g' $ASM/*
sed -ie 's/asm-sparc/asm/g' $ASM/*
***

The rest was an update of the top-level Makefile to use sparc
for header files when sparc64 is being build.
And a small fixlet to pick up the correct unistd.h from
sparc64 code.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>

arch/sparc/include/asm/irqflags_32.h

@@ -0,0 +1,39 @@
+/*
+ * include/asm/irqflags.h
+ *
+ * IRQ flags handling
+ *
+ * This file gets included from lowlevel asm headers too, to provide
+ * wrapped versions of the local_irq_*() APIs, based on the
+ * raw_local_irq_*() functions from the lowlevel headers.
+ */
+#ifndef _ASM_IRQFLAGS_H
+#define _ASM_IRQFLAGS_H
+
+#ifndef __ASSEMBLY__
+
+extern void raw_local_irq_restore(unsigned long);
+extern unsigned long __raw_local_irq_save(void);
+extern void raw_local_irq_enable(void);
+
+static inline unsigned long getipl(void)
+{
+        unsigned long retval;
+
+        __asm__ __volatile__("rd        %%psr, %0" : "=r" (retval));
+        return retval;
+}
+
+#define raw_local_save_flags(flags) ((flags) = getipl())
+#define raw_local_irq_save(flags)   ((flags) = __raw_local_irq_save())
+#define raw_local_irq_disable()     ((void) __raw_local_irq_save())
+#define raw_irqs_disabled()         ((getipl() & PSR_PIL) != 0)
+
+static inline int raw_irqs_disabled_flags(unsigned long flags)
+{
+        return ((flags & PSR_PIL) != 0);
+}
+
+#endif /* (__ASSEMBLY__) */
+
+#endif /* !(_ASM_IRQFLAGS_H) */