[Driver][Fuchsia] Support -nolibc flag

This can be used to disable libc linking. This flag is supported by
GCC since version 9 as well as some Clang target toolchains. This
change also includes tests for all -no* flags which previously weren't
covered.

Differential Revision: https://reviews.llvm.org/D58325

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@354208 91177308-0d34-0410-b5e6-96231b3b80d8