binder: Use common definition of SZ_1K

SZ_1K has been defined in include/linux/sizes.h since v3.6. Get rid of the
duplicate definition.

Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20191016150119.154756-2-jannh@google.com


Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>