chore: os-independent makefile to build werf target

Signed-off-by: Timofey Kirillov <timofey.kirillov@flant.com>

Makefile

@@ -1,12 +1,21 @@
 .PHONY: all werf buildah-test fmt lint docs clean build-images
 
+ifeq ($(OS),Windows_NT)
+    uname_S := Windows
+else
+    uname_S := $(shell uname -s)
+endif
+
 all: werf
 
+ifeq ($(uname_S), Linux)
+werf:
+	CGO_ENABLED=1 go install -compiler gc -ldflags="-linkmode external -extldflags=-static" -tags="dfrunmount dfssh containers_image_openpgp osusergo exclude_graphdriver_devicemapper netgo no_devmapper static_build" github.com/werf/werf/cmd/werf
+else
 werf:
 	CGO_ENABLED=0 go install -tags="dfrunmount dfssh containers_image_openpgp" "github.com/werf/werf/cmd/werf"
+endif
 
-buildah-werf:
-  CGO_ENABLED=1 go install -compiler gc -ldflags="-linkmode external -extldflags=-static" -tags="dfrunmount dfssh containers_image_openpgp osusergo exclude_graphdriver_devicemapper netgo no_devmapper static_build" github.com/werf/werf/cmd/werf
 
 buildah-test:
 	CGO_ENABLED=1 go install -compiler gc -ldflags="-linkmode external -extldflags=-static" -tags="dfrunmount dfssh containers_image_openpgp osusergo exclude_graphdriver_devicemapper netgo no_devmapper static_build" github.com/werf/werf/cmd/buildah-test