improve compatibility of make binaries (#3761)

scripts/binaries.mk

@@ -13,7 +13,7 @@ WORKDIR /s
 COPY go.mod go.sum ./
 RUN go mod download
 COPY . ./
-ENV CGO_ENABLED 0
+ENV CGO_ENABLED=0
 RUN rm -rf tmp binaries
 RUN mkdir tmp binaries
 RUN cp mediamtx.yml LICENSE tmp/
@@ -69,5 +69,5 @@ export DOCKERFILE_BINARIES
 binaries:
 	echo "$$DOCKERFILE_BINARIES" | DOCKER_BUILDKIT=1 docker build . -f - \
 	-t temp
-	docker run --rm -v "$(PWD):/out" \
+	docker run --rm -v "$(shell pwd):/out" \
 	temp sh -c "rm -rf /out/binaries && cp -r /s/binaries /out/"