x509.h.in: extended 'documenting' comment on X509_TRUST_OK_ANY_EKU
x509.h.in: extended 'documenting' comment on X509_TRUST_OK_ANY_EKU

This hopefully alleviates the fact that the name is unclear/misleading.

Reviewed-by: Paul Dale <ddec78389666b4f7c9b4d110380c848489a3e4aa@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/13735)

openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl,openssl/openssl