crypto/x509: fix typo in docs for CreateCertificateRequest

Update the doc for CreateCertificateRequest
to state that it creates a
  `new certificate request`
instead of just a
  `new certificate`

Fixes #14649.

Change-Id: Ibbbcf91d74168998990990e78e5272a6cf294d51
Reviewed-on: https://go-review.googlesource.com/23204Reviewed-by: Russ Cox <rsc@golang.org>

src/crypto/x509/x509.go

@@ -1853,8 +1853,8 @@ func parseCSRExtensions(rawAttributes []asn1.RawValue) ([]pkix.Extension, error)
 	return ret, nil
 }
 
-// CreateCertificateRequest creates a new certificate based on a template. The
-// following members of template are used: Subject, Attributes,
+// CreateCertificateRequest creates a new certificate request based on a template.
+// The following members of template are used: Subject, Attributes,
 // SignatureAlgorithm, Extensions, DNSNames, EmailAddresses, and IPAddresses.
 // The private key is the private key of the signer.
 //