clk: qcom: gcc-msm8939: use ARRAY_SIZE instead of specifying num_parents

Use ARRAY_SIZE() instead of manually specifying num_parents. This makes
adding/removing entries to/from parent_data easy and errorproof.

Signed-off-by: Dmitry Baryshkov <[email protected]>
Reviewed-by: Bryan O'Donoghue <[email protected]>
Signed-off-by: Bjorn Andersson <[email protected]>
Link: https://lore.kernel.org/r/[email protected]

Author: lumag