hg: panama/dev: fix missing imports after merge

[maurizio.cimadamore at oracle.com]

Changeset: 1270409ef704
Author:    mcimadamore
Date:      2018-03-01 12:51 +0000
URL:       http://hg.openjdk.java.net/panama/dev/rev/1270409ef704

fix missing imports after merge

! src/hotspot/cpu/x86/methodHandles_x86.cpp
! src/hotspot/cpu/x86/sharedRuntime_x86_64.cpp
! src/hotspot/share/runtime/codeSnippet.cpp