hg: build-infra/jdk9/hotspot: Use new style for mkdir/loginfo in gensrc.

[magnus.ihse.bursie at oracle.com]

Changeset: 947162b867cb
Author:    ihse
Date:      2016-01-19 11:25 +0100
URL:       http://hg.openjdk.java.net/build-infra/jdk9/hotspot/rev/947162b867cb

Use new style for mkdir/loginfo in gensrc.

! makefiles/GenerateSources.gmk
! makefiles/GensrcAdlc.gmk
! makefiles/GensrcDtrace.gmk
! makefiles/GensrcJvmti.gmk