mmc: sdhci: Remove redundant ADMA page boundary warnings

The bounce buffer, used for misaligned bytes for ADMA access,
resides wholly within the (align_sz)-aligned word, just by construction.
The page addresses are aligned to (align_sz), either for 4 or 8 bytes
alignment, so that the aligned word resides wholly within a single page
and can't cross the page boundary. So, the bounce buffer can't cross
the page boundary too. That's why the warnings are never hit, and can
be safely removed.

Signed-off-by: Andrew Gabbasov <andrew_gabbasov@mentor.com>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>