[7u-dev] Request for approval for 8058936 hotspot/test/Makefile should use jtreg script from $JT_HOME/bin/jreg (instead of $JT_HOME/win32/bin/jtreg)

[Staffan Larsen]

Please approve this backport from 9 and 8u. The fix applies cleanly.

bug: https://bugs.openjdk.java.net/browse/JDK-8058936
jdk9 changeset: http://hg.openjdk.java.net/jdk9/hs-rt/hotspot/rev/01961999c58a
review thread: 
http://mail.openjdk.java.net/pipermail/hotspot-dev/2014-September/015409.html

Thanks,
/Staffan