Refactored Makefile to allow building of different architectures separately

Makefile

-all: bridge-netdev
+i386: bridge-netdev
 	dd if=/dev/zero of=swap bs=1048576 count=1024
 	chmod 600 swap
 	mkswap swap
 	swapon swap
 
 	tar xf qemu-4.1.1.tar.xz
-	cd qemu-4.1.1 && ./configure --prefix=/usr
+	cd qemu-4.1.1 && ./configure --prefix=/usr --target-list=i386-softmmu,i386-linux-user
+	$(MAKE) -C qemu-4.1.1
+	$(MAKE) -C qemu-4.1.1 check
+	$(MAKE) -C qemu-4.1.1 install
+	rm -rf qemu-4.1.1
+
+	swapoff swap
+	rm -rf swap
+
+	echo "$$BRIDGE_NETDEV" > /etc/systemd/network/br0.netdev
+
+x86_64: bridge-netdev
+	dd if=/dev/zero of=swap bs=1048576 count=1024
+	chmod 600 swap
+	mkswap swap
+	swapon swap
+
+	tar xf qemu-4.1.1.tar.xz
+	cd qemu-4.1.1 && ./configure --prefix=/usr --target-list=x86_64-softmmu,x86_64-linux-user
 	$(MAKE) -C qemu-4.1.1
 	$(MAKE) -C qemu-4.1.1 check
 	$(MAKE) -C qemu-4.1.1 install
@@ -18,6 +36,42 @@ all: bridge-netdev
 
 	echo "$$BRIDGE_NETDEV" > /etc/systemd/network/br0.netdev
 
+arm: bridge-netdev
+	dd if=/dev/zero of=swap bs=1048576 count=1024
+	chmod 600 swap
+	mkswap swap
+	swapon swap
+
+	tar xf qemu-4.1.1.tar.xz
+	cd qemu-4.1.1 && ./configure --prefix=/usr --target-list=arm-softmmu,arm-linux-user,armeb-linux-user
+	$(MAKE) -C qemu-4.1.1
+	$(MAKE) -C qemu-4.1.1 check
+	$(MAKE) -C qemu-4.1.1 install
+	rm -rf qemu-4.1.1
+
+	swapoff swap
+	rm -rf swap
+
+	echo "$$BRIDGE_NETDEV" > /etc/systemd/network/br0.netdev
+
+aarch64: bridge-netdev
+	dd if=/dev/zero of=swap bs=1048576 count=1024
+	chmod 600 swap
+	mkswap swap
+	swapon swap
+
+	tar xf qemu-4.1.1.tar.xz
+	cd qemu-4.1.1 && ./configure --prefix=/usr --target-list=aarch64-softmmu,aarch64-linux-user,aarch64_be-linux-user
+	$(MAKE) -C qemu-4.1.1
+	$(MAKE) -C qemu-4.1.1 check
+	$(MAKE) -C qemu-4.1.1 install
+	rm -rf qemu-4.1.1
+
+	swapoff swap
+	rm -rf swap
+
+	echo "$$BRIDGE_NETDEV" > /etc/systemd/network/br0.netdev
+
 bridge-netdev:
 define BRIDGE_NETDEV
 [NetDev]