(11) RFR (S) JDK-8198312: VS2017: Upgrade HOTSPOT_BUILD_COMPILER in vm_version.cpp

[Lois Foltan]

Please review this small fix to set HOTSPOT_BUILD_COMPILER correctly for 
VS2017.

open webrev at http://cr.openjdk.java.net/~lfoltan/bug_jdk8198312/webrev/
bug link https://bugs.openjdk.java.net/browse/JDK-8198312
Testing: hs-tier(1-3), jdk-tier(1-3) complete

Thanks,
Lois