New host gcc prebuilt for MacOSX

Built from toolchain repo gcc.git/gcc-4.2.1-5666.3 (originally from
http://opensource.apple.com/tarballs/gcc/gcc-5666.3.tar.gz)

Do the following in source directory twice: both in MacOSX 10.6
and in MacOSX 10.7 systems

  mkdir -p build/obj build/dst build/sym
  gnumake install RC_OS=macos RC_ARCHS='i386 x86_64' \
    TARGETS='i386 x86_64' SRCROOT=pwd OBJROOT=pwd/build/obj \
    DSTROOT=pwd/build/dst SYMROOT=pwd/build/sym

Merge both build/dst/usr and remove unneeded files, add
*-gcc/g++/cpp links.

Change-Id: I946a95a4cd6aace31c4f1c6ffa76eada06d6e161
am c3d49ddd: Merge from AOSP

* commit 'c3d49ddd224af8d6d89c8c95b229758a2f090c8d':
  New host gcc prebuilt for MacOSX
Fix for clang -fsyntax-only happens to see the same header as host gcc

Change-Id: I110dff1c9b8d28a4110b5aa9a97619a74e1f2f1b
Merge "Fix for clang -fsyntax-only happens to see the same header as host gcc"