crypto: recognize raw formats in keygen

[panva]

Follow up to #62240, this needs no doc changes since

If a publicKeyEncoding or privateKeyEncoding was specified, this function behaves as if keyObject.export() had been called on its result.

[nodejs-github-bot]

Review requested:

• @nodejs/crypto
• @nodejs/security-wg

[codecov]

Codecov Report

❌ Patch coverage is 77.95276% with 28 lines in your changes missing coverage. Please review.
✅ Project coverage is 89.70%. Comparing base (8ea96e6) to head (69ae6f4).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
src/crypto/crypto_keys.cc	73.49%	9 Missing and 13 partials ⚠️
lib/internal/crypto/keys.js	86.36%	5 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #62480      +/-   ##
==========================================
- Coverage   91.55%   89.70%   -1.85%     
==========================================
  Files         350      691     +341     
  Lines      147610   214071   +66461     
  Branches    23212    41089   +17877     
==========================================
+ Hits       135139   192025   +56886     
- Misses      12217    14098    +1881     
- Partials      254     7948    +7694     

Files with missing lines	Coverage Δ
lib/internal/crypto/keys.js	95.46% <86.36%> (-0.35%)	⬇️
src/crypto/crypto_keys.cc	72.02% <73.49%> (ø)

... and 461 files with indirect coverage changes

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