sparc32: remove cast from output constraints in math asm statements

The following asm statements generated a sparse warning:

asm("addcc \n\t" : "=r" (((USItype)(r2)))

warning: asm output is not an lvalue

When asking on the sparse mailing list Linus replyed:

"
Those casts to (USItype) are all pointless to begin with (since the
values are of that type already!) and they mean that the expression
isn't something you can assign to (lvalue).
"

In the math emulation code drop all casts in the output
parts of the asm statements.

This fixes a lot of "warning: asm output is not an lvalue" sparse
warnings in math_32.c.

Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

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>