The prototypes in the header were changed by commit 4ac8f8e0 but the
functions no longer match. Correct this.

It seems odd that block devices take an lbaint_t for the block count, but
an unsigned long for the blknr. Surely we should promote blknr to lbaint_t
also?
Signed-off-by: NSimon Glass <sjg@chromium.org>
Reviewed-by: NTom Rini <trini@ti.com>