sparse: update __builtin_object_size() prototype

sparse: update __builtin_object_size() prototype

Sparse emits a large number of warnings for the linux kernel source
tree of the form:
    ./arch/x86/include/asm/uaccess.h:735:18: \
        warning: incorrect type in argument 1 (different modifiers)
    ./arch/x86/include/asm/uaccess.h:735:18:    expected void *<noident>
    ./arch/x86/include/asm/uaccess.h:735:18:    got void const *from

Fix by making the first parameter to __builtin_object_size()
type "const void *" instead of "void *", which is consistent with GCC
behavior (the prototype for this builtin in GCC documentation is evidently
incorrect).

Signed-off-by: Lance Richardson <lrichard@redhat.com>
Acked-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Signed-off-by: Christopher Li <sparse@chrisli.org>