Update alpine package

- minor cleanup
- remove cross compile support from go-compile script as not needed

Signed-off-by: Justin Cormack <justin.cormack@docker.com>

tools/alpine/Dockerfile

@@ -27,7 +27,7 @@ RUN echo "/mirror" > /etc/apk/repositories && apk update
 
 # add Go validation tools
 COPY go-compile.sh /go/bin/
-RUN apk add --no-cache build-base git go
+RUN apk add --no-cache git go musl-dev
 ENV GOPATH=/go PATH=$PATH:/go/bin
 RUN go get -u github.com/golang/lint/golint
 RUN go get -u github.com/gordonklaus/ineffassign

tools/alpine/go-compile.sh

@@ -33,14 +33,4 @@ go test
 
 export CGO_ENABLED=0
 
-if [ "$GOOS" = "darwin" -o "$GOOS" = "windows" ]
+go install -buildmode pie -ldflags "-s -w ${ldflags} -extldflags \"-fno-PIC -static\""
-then
-	if [ -z "$ldflags" ]
-	then
-		go install
-	else
-		go install -ldflags "${ldflags}"
-	fi
-else
-	go install -buildmode pie -ldflags "-s -w ${ldflags} -extldflags \"-fno-PIC -static\""
-fi

tools/alpine/versions

@@ -113,7 +113,7 @@ lzo-2.10-r0
 m4-1.4.18-r0
 make-4.2.1-r0
 mesa-gbm-17.0.3-r1
-mkinitfs-3.0.9-r1
+mkinitfs-3.1.0_rc1-r0
 mpc1-1.0.3-r0
 mpfr3-3.1.5-r0
 mtools-4.0.18-r1
@@ -136,7 +136,7 @@ patch-2.7.5-r1
 pcre-8.40-r2
 perl-5.24.1-r2
 pixman-0.34.0-r0
-pkgconf-1.3.6-r0
+pkgconf-1.3.7-r0
 popt-1.16-r6
 qemu-2.8.1-r1
 qemu-aarch64-2.8.1-r1