fix: fixed issues in TPM attestation for ECC

[podlesrafal]

Motivation:

fixed issues in TPM attestation for ECC: buffer position, reading x and y, parsing crv, compare curveId

Conformance:

You should have signed the Eclipse Contributor Agreement as explained in https://github.com/eclipse/vert.x/blob/master/CONTRIBUTING.md Please also make sure you adhere to the code style guidelines: https://github.com/vert-x3/wiki/wiki/Vert.x-code-style-guidelines