Make ETHOSN backend disabled by default

* Use ARMNN_ETHOS_ENABLE variable to enable it

Signed-off-by: Kevin May <kevin.may@arm.com>
Change-Id: I5465b7738556604367262cf9aa8e1ce6e01639b9
diff --git a/Android.mk b/Android.mk
index d7ee542..21ef136 100644
--- a/Android.mk
+++ b/Android.mk
@@ -86,7 +86,7 @@
 ARMNN_COMPUTE_CL_ENABLED := 1
 ARMNN_COMPUTE_NEON_ENABLED := 1
 ARMNN_REF_ENABLED := 1
-ARMNN_ETHOSN_ENABLED := 1
+ARMNN_ETHOSN_ENABLED := 0
 
 ifeq ($(ARMNN_COMPUTE_CL_ENABLE),0)
 ARMNN_COMPUTE_CL_ENABLED := 0
@@ -100,8 +100,8 @@
 ARMNN_REF_ENABLED := 0
 endif
 
-ifeq ($(ARMNN_ETHOSN_ENABLE),0)
-ARMNN_ETHOSN_ENABLED := 0
+ifeq ($(ARMNN_ETHOSN_ENABLE),1)
+ARMNN_ETHOSN_ENABLED := 1
 endif
 
 # Variable to control inclusion of libOpenCL shared library