powerpc: Move include files to arch/powerpc/include/asm

from include/asm-powerpc.  This is the result of a

mkdir arch/powerpc/include/asm
git mv include/asm-powerpc/* arch/powerpc/include/asm

Followed by a few documentation/comment fixups and a couple of places
where <asm-powepc/...> was being used explicitly.  Of the latter only
one was outside the arch code and it is a driver only built for powerpc.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

arch/powerpc/include/asm/i8259.h

@@ -0,0 +1,17 @@
+#ifndef _ASM_POWERPC_I8259_H
+#define _ASM_POWERPC_I8259_H
+#ifdef __KERNEL__
+
+#include <linux/irq.h>
+
+#ifdef CONFIG_PPC_MERGE
+extern void i8259_init(struct device_node *node, unsigned long intack_addr);
+extern unsigned int i8259_irq(void);
+extern struct irq_host *i8259_get_host(void);
+#else
+extern void i8259_init(unsigned long intack_addr, int offset);
+extern int i8259_irq(void);
+#endif
+
+#endif /* __KERNEL__ */
+#endif /* _ASM_POWERPC_I8259_H */