RFR: JDK-8319382: com/sun/jdi/JdwpAllowTest.java shows failures on AIX if prefixLen of mask is larger than 32 in IPv6 case

[Matthias Baesken]

In parseAllowedMask (file socketTransport.c) , prefixLen of mask is compared with a maxValue (32 for IPv4, 128 otherwise). This fails on AIX if it is larger than 32, because getaddrinfo seems to often (always ?) detect IPv4 family, even for IPv6 addresses, so we take the wrong maxValue.
Probably we have to adjust the allowed maxValue on AIX, or adjust the IPv6 check.

Example:
images/jdk/bin/java -agentlib:jdwp=transport=dt_socket,server=y,suspend=n,address=*:0,allow=0:0:0:0:0:0:10:0/106
Error in allow option: '106'
ERROR: transport error 103: invalid netmask in allow option
ERROR: JDWP Transport dt_socket failed to initialize, TRANSPORT_INIT(510)

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Commit messages:
 - JDK-8319382

Changes: https://git.openjdk.org/jdk/pull/16561/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk&pr=16561&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8319382
  Stats: 6 lines in 1 file changed: 6 ins; 0 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/16561.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16561/head:pull/16561

PR: https://git.openjdk.org/jdk/pull/16561