staging: android: Split uapi out of binder.h

Move the userspace interface of binder.h to
drivers/staging/android/uapi/binder.h.

Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Colin Cross <ccross@android.com>
Cc: Android Kernel Team <kernel-team@android.com>
Signed-off-by: Colin Cross <ccross@android.com>
[jstultz: Worked out the collisions from some of the type changes
made upstream. Also minor commit subject tweak]
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>