Import upstream 19d378f44:
ASN.1 INTEGERs will now compile to C int64_t or uint64_t, depending on whether the constraint ranges include numbers that cannot be represented in 32-bit ints and whether they include negative numbers. Template backend support included. check-template is now built with --template, so we know we're testing it. Tests included.
This should ensure generated asn1 headers (cms_asn1.h, krb5_asn1.h etc)
are the same for 64-bit and 32-bit hosts. In particular, cross-building
i386 from amd64 should result in exactly the same asn1 headers as a
native i386 build.
Obtained from: upstream 19d378f44
MFC after: TBD