mail-filter/opendkim: Increase keysize to 2048 bits

As recommended by RFC 8301 section 3.2:

  Signers MUST use RSA keys of at least 1024 bits for all keys.
  Signers SHOULD use RSA keys of at least 2048 bits.

Closes: https://bugs.gentoo.org/962174
Acked-by: Michael Orlitzky <mjo@gentoo.org>
Signed-off-by: Ulrich Müller <ulm@gentoo.org>

mail-filter/opendkim/opendkim-2.10.3-r35.ebuild

@@ -226,7 +226,7 @@ pkg_config() {
 	if [[ -f "${ROOT}/var/lib/opendkim/${selector}.private" ]]; then
 		ewarn "The private key for this selector already exists."
 	else
-		keysize=1024
+		keysize=2048
 		# Generate the private and public keys. Note that opendkim-genkeys
 		# sets umask=077 on its own to keep these safe. However, we want
 		# them to be readable (only!) to the opendkim user, and we manage