[Interest] distinguish nmake and sln generators in qmake script

[Vyacheslav Lanovets]

Hi

What is the best way to distinguish between Visual Studio Solution
vcxproj generator (Src\qtbase\qmake\generators\win32\msvc_vcproj.cpp
described in https://doc.qt.io/qt-5/qmake-platform-notes.html#creating-visual-studio-project-files)
and Makefile nmake generator (qmake\generators\win32\msvc_nmake.cpp)
inside pri/pro script?

I use this check
contains(TEMPLATE, "^vc.+")

Am I right?