It doesn't look like there is anything llvm-lib needs to handle based on
Microsoft's description of the flag.
https://docs.microsoft.com/en-us/cpp/build/reference/managing-a-library?view=msvc-170
Reviewed By: thakis
Differential Revision: https://reviews.llvm.org/D129032
//==============================================================================
def ltcg : F<"ltcg">;
+def nodefaultlib: P<"nodefaultlib", "">;
+def nodefaultlib_all: F<"nodefaultlib">;
def nologo : F<"nologo">;
def subsystem : P<"subsystem", "">;