[CMake] Fixes /INCREMENTAL detection when considering adding /Brepro

/INCREMENTAL is the linker default (lld-link and MSVC link). Specifying
"/INCREMENTAL:NO" is the only way to disable it. So checking for the
negative flag instead and check exe/module/shared link flags
independently.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D117381