RFR: JDK-8047019 - Implement javacall_logging_printf function

[Jen Dority]

issue: https://bugs.openjdk.java.net/browse/JDK-8047019
webrev: http://cr.openjdk.java.net/~jld/8047019/webrev/

Hi,

This is a small change to implement the native logging in the DIO code.

This code is used when setting JAVACALL_REPORT_LEVEL < 4 in Makefile.

Thanks,
Jen