am 7852b80c: Merge "Add missing flags to x86 (both 32- and 64-bit) arch variants. Delete x86_64-atom.mk as we don\'t support 64-bit on old Atom."

* commit '7852b80c05e33c873819b1bf22bcaa54bb583c99':
  Add missing flags to x86 (both 32- and 64-bit) arch variants. Delete x86_64-atom.mk as we don't support 64-bit on old Atom.