Dynamic selection of ECDSA or RSA

Add new option rsa+ecdsa for TF_MBEDTLS_KEY_ALG, which selects
rsa or ecdsa depending on the certificate used.

Change-Id: I08d9e99bdbba361ed2ec5624248dc382c750ad47
Signed-off-by: Qixiang Xu <qixiang.xu@arm.com>
4 files changed