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/processor.h

@@ -0,0 +1,8 @@
+#ifndef ___ASM_SPARC_PROCESSOR_H
+#define ___ASM_SPARC_PROCESSOR_H
+#if defined(__sparc__) && defined(__arch64__)
+#include <asm/processor_64.h>
+#else
+#include <asm/processor_32.h>
+#endif
+#endif