ledc_types.h includes two similar enums, ledc_clk_src_t & ledc_clk_cfg_t. Latter was added in
ESP-IDF v4.0.
The two enums do different things but there are two similar names: LEDC_REF_TICK / LEDC_USE_REF_TICK
and LEDC_APB_CLK / LEDC_USE_APB_CLK.
Because C will accept any enum or integer value for an enum argument, there's no easy way to check
the correct enum is passed without using static analysis.
To avoid accidental errors, make the numeric values for the two similarly named enums the same.,
Noticed when looking into https://github.com/espressif/esp-idf/issues/4476
