Reverting to the old way of getting the abi on Android

uname is not available on all Android devices, and we cannot rely on
busybox for establishing the ABI, as we need to get the ABI before we
can depoly the right version of busybox.

wlauto/common/android/device.py

@@ -96,6 +96,10 @@ class AndroidDevice(BaseLinuxDevice):  # pylint: disable=W0223
                 self._is_rooted = False
         return self._is_rooted
 
+    @property
+    def abi(self):
+        return self.getprop()['ro.product.cpu.abi'].split('-')[0]
+
     @property
     def supported_eabi(self):
         props = self.getprop()

wlauto/common/linux/device.py

@@ -115,7 +115,7 @@ class BaseLinuxDevice(Device):  # pylint: disable=abstract-method
     @property
     def abi(self):
         if not self._abi:
-            val = self.execute('uname -m', busybox=True).strip()
+            val = self.execute('uname -m').strip()
             for abi, architectures in ABI_MAP.iteritems():
                 if val in architectures:
                     self._abi = abi