libnet_join: add SPNs for additional-dns-hostnames entries

and set msDS-AdditionalDnsHostName to the specified list.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=14116

Signed-off-by: Isaac Boukris <[email protected]>
Reviewed-by: Ralph Boehme <[email protected]>
Reviewed-by: Alexander Bokovoy <[email protected]>

Autobuild-User(master): Ralph Böhme <[email protected]>
Autobuild-Date(master): Fri Oct 25 10:43:08 UTC 2019 on sn-devel-184
22 jobs for iboukris-v4-10-test in 209 minutes and 3 seconds (queued for 4 seconds)
latest
Status Job ID Name Coverage
  Build
passed #334826757
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build_ctdb

00:32:56

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build_others

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build_samba

03:28:51

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build_samba_ad_dc

01:16:03

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build_samba_ad_dc_2

00:29:01

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build_samba_ad_dc_2_py2

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build_samba_ad_dc_backup

00:32:16

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build_samba_ad_dc_backup_py2

00:21:22

passed #334826768
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build_samba_ad_dc_py2

00:19:12

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build_samba_buildpy2_only

00:16:23

passed #334826758
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build_samba_ctdb

00:18:50

passed #334826766
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build_samba_fileserver

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passed #334826754
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build_samba_libs

00:27:22

passed #334826755
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build_samba_libs_py2

00:33:57

passed #334826744
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build_samba_none_env

00:47:01

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build_samba_none_env_py2

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passed #334826746
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build_samba_nopython

00:24:58

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build_samba_o3

00:30:41

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build_samba_py2

01:05:07

passed #334826756
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build_samba_static

00:41:39

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build_samba_systemkrb5

00:13:10

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build_samba_xc

00:05:04