Staging: android: binder: Support concurrent 32 bit and 64 bit processes.

Add binder_size_t and binder_uintptr_t that is used instead of size_t and
void __user * in the user-space interface.

Use 64 bit pointers on all systems unless CONFIG_ANDROID_BINDER_IPC_32BIT
is set (which enables the old protocol on 32 bit systems).

Change BINDER_CURRENT_PROTOCOL_VERSION to 8 if
CONFIG_ANDROID_BINDER_IPC_32BIT is not set.

Add compat ioctl.

Change-Id: Ifbbde0209da0050011bcab34c547a4c30d6e8c49
Signed-off-by: Arve Hjønnevåg <arve@android.com>