bugfix: fix a nil deference in transport key provider package (#675)
bugfix: fix a nil deference in transport key provider package (#675)

NB: we can just self bootstrap by using the incoming csr.CertificateRequest
drcapulet/cfssl,geligaoli/cfssl,drcapulet/cfssl,sfurman3/cfssl,geligaoli/cfssl,drcapulet/cfssl,cloudflare/cfssl,sfurman3/cfssl,cloudflare/cfssl,drcapulet/cfssl,cloudflare/cfssl,drcapulet/cfssl,geligaoli/cfssl,sfurman3/cfssl,geligaoli/cfssl,cloudflare/cfssl,geligaoli/cfssl,sfurman3/cfssl,sfurman3/cfssl