Make adbs work again on Darwin x86.

We don't support building on Darwin PPC so let's always assume x86.

Change-Id: I079a4040f1c0a144d4cdd1e2b3d2a183c00bf7b0
diff --git a/tools/adbs b/tools/adbs
index b571d48..1a400f7 100755
--- a/tools/adbs
+++ b/tools/adbs
@@ -137,11 +137,7 @@
 
   uname = os.uname()[0]
   if uname == "Darwin":
-    proc = os.uname()[-1]
-    if proc == "i386":
-      uname = "darwin-x86"
-    else:
-      uname = "darwin-ppc"
+    uname = "darwin-x86"
   elif uname == "Linux":
     uname = "linux-x86"
   prefix = "./prebuilt/" + uname + "/toolchain/arm-linux-androideabi-4.4.x/bin/"