x509/cert: reorganized and split credentials and session certificate functions

Signed-off-by: Nikos Mavrogiannopoulos <nmav@redhat.com>
15 jobs from tmp-draft-ietf-tls-tls13-21-nmav-backports6 in 94 minutes and 41 seconds (queued for 9 seconds)
Status Job ID Name Coverage
  Stage1 Testing
passed #41765764
aarch64
Debian.aarch64

00:20:22

passed #41765763
shared
Debian.x86_64

00:35:45

passed #41765751
shared
FIPS140-2.Fedora.x86_64

01:14:58

passed #41765760
shared
Fedora.x86

00:32:10

passed #41765759
freebsd
FreeBSD.x86_64

00:16:21

passed #41765758
shared docker
MinGW32

00:10:33

passed #41765757
shared docker
MinGW64

00:13:17

passed #41765748
shared
abi-coverage.Fedora

00:36:39

77.9%
passed #41765754
shared
asan.Fedora.x86_64

01:12:23

passed #41765747
shared
doc-dist.Fedora

00:33:01

passed #41765749
shared
minimal.Fedora.x86_64

00:38:14

passed #41765750
shared
no-SSL-3.0.Fedora.x86_64

00:19:24

passed #41765755
shared
static-analyzers.Fedora.x86_64

00:21:25

passed #41765762
shared
ubsan-Werror.Fedora.x86_64

01:19:23

passed #41765753
shared
valgrind.Fedora.x86_64

00:34:08