Remove all /machine:I386 references, these are getting in the way
  of switching linkers from the x86 (default linker) to x64 or other
  possible target platforms.  (Also this commit cleans up lingering
  /GX switches from the 'BASE' options that are supposed to be unused.)

Backports: 397407

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/branches/2.2.x@397649 13f79535-47bb-0310-9956-ffa450edef68