sm: Support generation of card-based ECDSA CSR.
* sm/call-agent.c (gpgsm_scd_pksign): Identify type of signing key and format resulting S-expression accordingly.
Current GpgSM implementation assumes card-based keys are RSA keys.
This patch introduces support for ECDSA keys.
(cherry picked from commit 74e9b579ca273fc07be090bb5fb7800a97b1b452)
- Removed already applied changes from the original commit.
- Allow for SHA384 and SHA512
- GnuPG-bug-id: T4092
- Signed-off-by: Werner Koch <wk@gnupg.org>