Modify Makefile to support building for ARM64 architecture

Makefile

@@ -1,7 +1,16 @@
 CTR=docker
 NAME=woom
+
+GOOS ?= linux
+GOARCH ?= amd64
+
 GOBUILD=CGO_ENABLED=0 \
-				go build -tags release -trimpath
+	GOOS=$(GOOS) GOARCH=$(GOARCH) \
+		go build -tags release -trimpath
+
+GOBUILDARM64=CGO_ENABLED=0 \
+	GOOS=$(GOOS) GOARCH=arm64 \
+		go build -tags release -trimpath
 
 .PHONY: default
 default: webapp build
@@ -10,13 +19,20 @@ default: webapp build
 build:
 	$(GOBUILD) -o $(NAME)
 
+.PHONY: build-arm64
+build-arm64:
+	$(GOBUILDARM64) -o $(NAME)-aarch64
+
+.PHONY: arm64
+arm64: webapp build-arm64
+
 .PHONY: webapp
 webapp:
 	npm run build
 
 .PHONY: webapp-clean
 webapp-clean:
-	rm -r dist
+	rm -r static/dist
 
 .PHONY: clean
 clean: webapp-clean