Refresh ARM toolchain to GCC 4.7 / binutils 2.22.

Change-Id: Id3689376ae4c4fc183569955b2ee98df5c069510
diff --git a/envsetup.sh b/envsetup.sh
index 2d9d245..3aeb52b 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -116,7 +116,7 @@
     prebuiltdir=$(getprebuilt)
     gccprebuiltdir=$(get_abs_build_var ANDROID_GCC_PREBUILTS)
 
-    # defined in core/config.mk
+    # defined in core/combo/TARGET_linux-{arm,mips,x86}.mk
     targetgccversion=$(get_build_var TARGET_GCC_VERSION)
     export TARGET_GCC_VERSION=$targetgccversion