Make release-linux archtectures via envs

Makefile

@@ -87,6 +87,8 @@ endif
 
 LDFLAGS := $(LDFLAGS) -X "main.MakeVersion=$(MAKE_VERSION)" -X "main.Version=$(GITEA_VERSION)" -X "main.Tags=$(TAGS)"
 
+LINUX_ARCHS ?= linux/amd64,linux/386,linux/arm-5,linux/arm-6,linux/arm64
+
 GO_PACKAGES ?= $(filter-out code.gitea.io/gitea/integrations/migration-test,$(filter-out code.gitea.io/gitea/integrations,$(shell $(GO) list -mod=vendor ./... | grep -v /vendor/)))
 
 FOMANTIC_CONFIGS := semantic.json web_src/fomantic/theme.config.less web_src/fomantic/_site/globals/site.variables
@@ -583,7 +585,7 @@ release-linux: | $(DIST_DIRS)
 	@hash xgo > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
 		GO111MODULE=off $(GO) get -u src.techknowlogick.com/xgo; \
 	fi
-	CGO_CFLAGS="$(CGO_CFLAGS)" GO111MODULE=off xgo -go $(XGO_VERSION) -dest $(DIST)/binaries -tags 'netgo osusergo $(TAGS)' -ldflags '-linkmode external -extldflags "-static" $(LDFLAGS)' -targets 'linux/amd64,linux/386,linux/arm-5,linux/arm-6,linux/arm64' -out gitea-$(VERSION) .
+	CGO_CFLAGS="$(CGO_CFLAGS)" GO111MODULE=off xgo -go $(XGO_VERSION) -dest $(DIST)/binaries -tags 'netgo osusergo $(TAGS)' -ldflags '-linkmode external -extldflags "-static" $(LDFLAGS)' -targets '$(LINUX_ARCHS)' -out gitea-$(VERSION) .
 ifeq ($(CI),drone)
 	cp /build/* $(DIST)/binaries
 endif