cmake: correctly handle linker flags for static libs

cmake: correctly handle linker flags for static libs

curl CMake was setting the the EXE flags for static libraries which made
the /manifest:no flag ended up when linking the static library, which is
not a valid flag for lib.exe or llvm-lib.exe and caused llvm-lib to exit
with an error.

The better way to handle this is to make sure that we pass the correct
linker flags to CMAKE_STATIC_LINKER_FLAGS instead.

Reviewed-by: Jakub Zakrzewski
Closes #6195