[docs] Tweak phrasing of the varargs explanation in the command section of the
CMake primer.

This moves the introduction of the ARGV/ARGN variables up to immmediately follow
the introduction of the concept of variable argument functions, and explicitly
connects this concept to C varargs functions.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@311113 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed