crypto: support ECDHE when ec_point_formats is missing in ClientHello

[yang-wei]

As describe in rfc8422 5.1.2, we will support ECDHE in the case client does not
include ec_point_formats extension in ClientHello extension. This make sure ECDHE
will work with (uncompressed point format is listed explicitly) or without extension.

rfc8422 5.1.2: https://datatracker.ietf.org/doc/html/rfc8422#section-5.1.2.

Fixes #49126

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[torntrousers]

We've hit this in #53750, any idea when the fix might make it out in a release?