Remove custom PKCS7 ASN1 functions, add new structs #3169

Job	Run time
amazon-corretto-crypto-provider	17m 32s
bind9	5m 1s
grpc	24m 0s
haproxy	3m 3s
libevent	27m 44s
ntp	2m 17s
OpenLDAP	16m 49s
openvpn	3m 39s
Python main	3m 48s
Python releases (FIPS=0 OPENSSL_IN_CRT=0)	12m 31s
socat	9m 10s
Python releases (FIPS=1 OPENSSL_IN_CRT=0)	11m 38s
strongswan	1m 42s
tcpdump	1m 38s
Python releases (FIPS=0 OPENSSL_IN_CRT=1)	11m 38s
tpm2-tss	4m 1s
Python releases (FIPS=1 OPENSSL_IN_CRT=1)	13m 22s
trousers	1m 14s
	2h 50m 47s

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