mmc: sdhci-msm: Warn about overclocking SD/MMC

As talked about in commit 5e4b7e82 ("clk: qcom: gcc-sdm845: Use
floor ops for sdcc clks"), most clocks handled by the
Qualcomm Technologies, Inc. clock drivers are rounded _up_ by
default instead of down.  We should make sure SD/MMC clocks are
always rounded down in the clock drivers.
Let's add a warning in the Qualcomm Technologies, Inc. SDHCI
driver to help catch the problem.

This would have saved a bunch of time [1].

NOTE: this doesn't actually fix any problem, it just makes it obvious
to devs that there is a problem and that should be an indication to
fix the clock driver.

Change-Id: I0d7b15c854eb716383bee54715361d8936b6ad0f
Git-Repo: https://git.kernel.org/pub/scm/linux/kernel/git/ulfh/mmc.git/


Git-Commit: a8cd989e1a57dff3994cd113650afb0223c44ec6
Suggested-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Bjorn Andersson <bjorn.andersson@linaro.org>
Acked-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Sarthak Garg <sartgarg@codeaurora.org>