Revert "EVP_PKEY_asn1_add0(): Check that this method isn't already registered"

This reverts commit d85722d3

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Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
(Merged from https://github.com/openssl/openssl/pull/5137)

(cherry picked from commit 7203c94e)