Fix printk format warnings:
drivers/char/ftape/zftape/zftape-buffers.c:87: warning: format '%d' expects type
'int', but argument 3 has type 'size_t'
drivers/char/ftape/zftape/zftape-buffers.c:104: warning: format '%d' expects type
'int', but argument 3 has type 'size_t'