integrity: Allow sigv3 verification on EVM_XATTR_PORTABLE_DIGSIG Allow sigv3 verification on EVM_XATTR_PORTABLE_DIGSIG on RSA, ECDSA, ECRDSA, and SM2 signatures. Signed-off-by: Stefan Berger <stefanb@linux.ibm.com> Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>