Remove useless ARM variables in makefile

packet-exchange/build/Makefile

-ARM_CC = arm-linux-gnueabihf-gcc
-SERVER_ARM_PROG = server_arm
-CLIENT_ARM_PROG = client_arm
 SERVER_PROG = server
 CLIENT_PROG = client
 SRCDIR = ../src
@@ -19,7 +16,7 @@ SERVER_OBJS = $(SERVER_SRCS:%.c=%.o)
 CLIENT_OBJS = $(CLIENT_SRCS:%.c=%.o)
 
 ifeq ($(DEBUG),)
-CFLAGS = -O2 -Wall -Wextra
+CFLAGS = -O2
 else
 CFLAGS = -Og -g -Wall -Wextra
 endif
@@ -32,18 +29,6 @@ LDFLAGS = -pthread
 
 vpath %.c $(SRCDIR)
 
-$(SERVER_ARM_PROG): FORCE
-	make clean
-	make -e CC:=$(ARM_CC) $(SERVER_PROG)
-	mv $(SERVER_PROG) $(SERVER_ARM_PROG)
-
-$(CLIENT_ARM_PROG): FORCE
-	make clean
-	make -e CC:=$(ARM_CC) $(CLIENT_PROG)
-	mv $(CLIENT_PROG) $(CLIENT_ARM_PROG)
-
-FORCE:
-
 $(SERVER_PROG): $(SERVER_OBJS)
 	$(CC) $(LDFLAGS) $^ -o $@
 
@@ -54,7 +39,7 @@ $(CLIENT_PROG): $(CLIENT_OBJS)
 -include $(subst .c,.d,$(CLIENT_SRCS))
 
 clean:
-	$(RM) $(SERVER_OBJS) $(SERVER_PROG) $(SERVER_ARM_PROG) $(subst .c,.d,$(SERVER_SRCS))
-	$(RM) $(CLIENT_OBJS) $(CLIENT_PROG) $(CLIENT_ARM_PROG) $(subst .c,.d,$(CLIENT_SRCS))
+	$(RM) $(SERVER_OBJS) $(SERVER_PROG) $(subst .c,.d,$(SERVER_SRCS))
+	$(RM) $(CLIENT_OBJS) $(CLIENT_PROG) $(subst .c,.d,$(CLIENT_SRCS))
 
-.PHONY: clean FORCE
+.PHONY: clean