Remove unnecessary SONIC_ Make variables

Signed-off-by: Jipan Yang <jipan.yang@alibaba-inc.com>

Makefile.work

@@ -109,9 +109,9 @@ SONIC_BUILD_INSTRUCTION :=  make \
                            BUILD_TIMESTAMP=$(BUILD_TIMESTAMP) \
                            ENABLE_DHCP_GRAPH_SERVICE=$(ENABLE_DHCP_GRAPH_SERVICE) \
                            SHUTDOWN_BGP_ON_START=$(SHUTDOWN_BGP_ON_START) \
-                           SONIC_ENABLE_PFCWD_ON_START=$(ENABLE_PFCWD_ON_START) \
-                           SONIC_ENABLE_SYNCD_RPC=$(ENABLE_SYNCD_RPC) \
-                           SONIC_INSTALL_DEBUG_TOOLS=$(INSTALL_DEBUG_TOOLS) \
+                           ENABLE_PFCWD_ON_START=$(ENABLE_PFCWD_ON_START) \
+                           ENABLE_SYNCD_RPC=$(ENABLE_SYNCD_RPC) \
+                           INSTALL_DEBUG_TOOLS=$(INSTALL_DEBUG_TOOLS) \
                            PASSWORD=$(PASSWORD) \
                            USERNAME=$(USERNAME) \
                            SONIC_BUILD_JOBS=$(SONIC_BUILD_JOBS) \

slave.mk

@@ -73,22 +73,6 @@ list :
 ## Include other rules
 ###############################################################################
 
-ifeq ($(SONIC_ENABLE_PFCWD_ON_START),y)
-ENABLE_PFCWD_ON_START = y
-endif
-
-ifeq ($(SONIC_ENABLE_SYSTEM_TELEMETRY),y)
-ENABLE_SYSTEM_TELEMETRY = y
-endif
-
-ifeq ($(SONIC_ENABLE_SYNCD_RPC),y)
-ENABLE_SYNCD_RPC = y
-endif
-
-ifeq ($(SONIC_INSTALL_DEBUG_TOOLS),y)
-INSTALL_DEBUG_TOOLS = y
-endif
-
 include $(RULES_PATH)/config
 include $(RULES_PATH)/functions
 include $(RULES_PATH)/*.mk
@@ -545,7 +529,7 @@ $(addprefix $(TARGET_PATH)/, $(SONIC_INSTALLERS)) : $(TARGET_PATH)/% : \
 	$(HEADER)
 	# Pass initramfs and linux kernel explicitly. They are used for all platforms
 	export debs_path="$(STRETCH_DEBS_PATH)"
-	export python_debs_path="$(PYTHON_DEBS_PATH)" 
+	export python_debs_path="$(PYTHON_DEBS_PATH)"
 	export initramfs_tools="$(STRETCH_DEBS_PATH)/$(INITRAMFS_TOOLS)"
 	export linux_kernel="$(STRTCH_DEBS_PATH)/$(LINUX_KERNEL)"
 	export onie_recovery_image="$(FILES_PATH)/$(ONIE_RECOVERY_IMAGE)"