RFR: 8235834 IBM-943 charset encoder needs updating

[Ichiroh Takiguchi]

Hello.

Could you review the fix ?
Bug:    https://bugs.openjdk.java.net/browse/JDK-8235834
Change: https://cr.openjdk.java.net/~itakiguchi/8235834/webrev.00/

IBM-943 is for IBM Japanese PC encoding.
MS932 is for Microsoft Japanese Windows encoding.
IBM-943 charset encoder does not contain 5 compatible entries compared 
to MS932 charset.

Thanks,
Ichiroh Takiguchi
IBM Japan, Ltd.