[PATCH] m32r: make userspace headers platform-independent

The m32r kernel 2.6.18-rc1 or after cause build errors of "unknown isa
configuration" for userspace application programs, such as glibc, gdb, etc.

This is because the recent kernel do not include linux/config.h not to expose
kernel headers for userspace.

To fix the above compile errors, this patch fixes two headers ptrace.h and
sigcontext.h for m32r and makes them platform-independent.

Signed-off-by: Hirokazu Takata <takata@linux-m32r.org>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Chris Wright <chrisw@sous-sol.org>