Make read_otadata() in bootloader_utility public (IDFGH-10345)

[ddomnik]

Is your feature request related to a problem?

I use a custom bootloader to manually decide which app slot should be booted. To still use Espressifs image validation process after writing a new image, I want to find the image with the OTA state ESP_OTA_IMG_NEW. I see that read_otadata() would satisfy this need, but is not accessible.

Describe the solution you'd like.

Make read_otadata() from bootloader_utility.c accessible.

Describe alternatives you've considered.

No response

Additional context.

No response