refactor(ethos-n): move build flags to ethosn_npu.mk

The build flags to enable the Arm(R) Ethos(TM)-N NPU driver are in arm
platform specific make files i.e. plat/arm/common/arm_common.mk. These
flags are renamed and moved to ethosn_npu.mk. Other source and make
files are changed to reflect the changes in these flags.

Signed-off-by: Rajasekaran Kalidoss <rajasekaran.kalidoss@arm.com>
Change-Id: I6fd20225343c574cb5ac1f0f32ff2fc28ef37ea6
diff --git a/plat/arm/board/juno/platform.mk b/plat/arm/board/juno/platform.mk
index a4e6407..19091f3 100644
--- a/plat/arm/board/juno/platform.mk
+++ b/plat/arm/board/juno/platform.mk
@@ -43,8 +43,8 @@
 JUNO_TZMP1		:=	0
 $(eval $(call assert_boolean,JUNO_TZMP1))
 ifeq (${JUNO_TZMP1}, 1)
-  ifeq (${ARM_ETHOSN_NPU_TZMP1},1)
-    $(error JUNO_TZMP1 cannot be used together with ARM_ETHOSN_NPU_TZMP1)
+  ifeq (${ETHOSN_NPU_TZMP1},1)
+    $(error JUNO_TZMP1 cannot be used together with ETHOSN_NPU_TZMP1)
   else
     $(eval $(call add_define,JUNO_TZMP1))
   endif
@@ -207,6 +207,7 @@
 # Add the HW_CONFIG to FIP and specify the same to certtool
 $(eval $(call TOOL_ADD_PAYLOAD,${HW_CONFIG},--hw-config,${HW_CONFIG}))
 
+include drivers/arm/ethosn/ethosn_npu.mk
 include plat/arm/board/common/board_common.mk
 include plat/arm/common/arm_common.mk
 include plat/arm/soc/common/soc_css.mk