Enable armv7/thumb2 multilib for arm-eabi.

Configured multilib:

> arm-eabi-gcc -print-multi-lib
.;
thumb;@mthumb
thumb/thumb2;@mthumb@march=armv7

See 978fb74a5c086cc5572dc2e3f37d207acad969d7

Change-Id: Ia04c9e23cb5abb924702639c6c0f3afc9c485ff0
Backport a gimplify fix.

See
  http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55245
  6014e0c5342ece48f16f5b02f1b0657d2538a036

Change-Id: I25bfcfdbf0911f18db9b554012258f4d9aa060bd
Enable MIPS floating-point madd/msub/nmadd/nmsub/recip/rsqrt with 32-bit FPU.

See 7609f724df8ca390935f63243fa72e1de39d00c6

Change-Id: Id77b56a1cf886584020cf30a4211de0a87b4f56e
Fix ARM GCC fail to links code using 64-bit atomic built-in

For ARM w/o dmb a helper function is called for 64-bit atomic
built-in, which call __write when helper version is too old.
Change to call write instead for Android.

See http://code.google.com/p/android/issues/detail?id=41297
e42abc641966570528522d61ba625e926e979ac7

Change-Id: I15498b73eebdbd5f4d62aafa943290ca341378bb
Patch GCC libstdc++ to work with Clang in C++11

See http://clang.llvm.org/cxx_status.html
    http://code.google.com/p/android/issues/detail?id=39600
    https://android-review.googlesource.com/#/c/47836/
    1e4edc8addf7fc21d821e64cc81d85315561bcd9

Change-Id: Ibbc2ed2bf665bbdd9529e6d962312b10a0da320f