RFR: 8220281 IBM-858 alias name is missing on IBM00858 charset

[Ichiroh Takiguchi]

Hello.

Could you review the fix ?

Bug:    https://bugs.openjdk.java.net/browse/JDK-8220281
Change: https://cr.openjdk.java.net/~itakiguchi/8220281/webrev.00/

I'd like to obtain a sponsor for this issue.

en_US.IBM-858 was added into AIX 7.1 [1] and 7.2 [2]
IBM00858 charset was registered into IANA Character Sets. [3]
And Java already has IBM00858.
But IBM00858 charset has IBM-858 alias.
Because of this situation, JDK13 does not start on AIX en_US.IBM-858 
locale.

I'd like to request to add some charset aliases against following 
charsets:
   ibm00858, ibm01140, ibm01141, ibm01142, ibm01143, ibm01144,
   ibm01145, ibm01146, ibm01147, ibm01148, ibm01149, x-ibm833

[1] 
https://www.ibm.com/support/knowledgecenter/en/ssw_aix_71/com.ibm.aix.nlsgdrf/support_languages_locales.htm
[2] 
https://www.ibm.com/support/knowledgecenter/en/ssw_aix_72/com.ibm.aix.nlsgdrf/support_languages_locales.htm
[3] https://www.iana.org/assignments/character-sets/character-sets.xhtml

Thanks,
Ichiroh Takiguchi
IBM Japan, Ltd.