Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct spmi_pmic_div_clk_cc.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Bjorn Andersson <andersson@kernel.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Konrad Dybcio <konrad.dybcio@linaro.org>
Cc: Michael Turquette <mturquette@baylibre.com>
Cc: Stephen Boyd <sboyd@kernel.org>
Cc: linux-arm-msm@vger.kernel.org
Cc: linux-clk@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20230817202941.never.657-kees@kernel.orgReviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>