cargo-espflash's --erase-part option requires --partition-table even when the partition table is set via metadata

[codyps]

When passing --erase-part to cargo-espflash for a package that has a partition table in package metadata (ie: in Cargo.toml's [package.metadata.espflash] section), cargo-espflash still complains with:

error: the following required arguments were not provided:
  --partition-table <FILE>

Instead of returning an error, cargo-espflash should use the partition table provided by the metadata when a partition erase is requested (if that metadata is present for the package used).

[SergioGasquez]

I've peeked into this issue, and there is some entangling to solve. Both --erase-parts and --erase-data-parts require --partition-table since in espflash we dont access the Cargo.toml, hence we can't read the partition from there. In cargo-espflash we reuse the FlashArgs defined in espflash.

One possible solution would be to remove the requirement of --partition-table and improve the error message when it's not supplied suggesting that you may have missed adding it.

• This would mean the error occurs when trying to erase the partitions and not when checking the cli args like right now.
• Not a really clean approach for the above reasons.