Update Makefile

Author: mgiessing

Makefile

@@ -39,7 +39,7 @@ build: validate-go-version clean $(BINARY)
 $(BINARY):
 	CGO_ENABLED=0 $(GO) build -a -installsuffix cgo -ldflags="-X main.VERSION=${VERSION}" -o $@ github.com/oauth2-proxy/oauth2-proxy/v7
 
-DOCKER_BUILD_PLATFORM ?= linux/amd64,linux/arm64,linux/arm/v6
+DOCKER_BUILD_PLATFORM ?= linux/amd64,linux/arm64,linux/ppc64le,linux/arm/v6
 DOCKER_BUILDX_ARGS ?=
 DOCKER_BUILDX := docker buildx build ${DOCKER_BUILDX_ARGS} --build-arg VERSION=${VERSION}
 DOCKER_BUILDX_X_PLATFORM := $(DOCKER_BUILDX) --platform ${DOCKER_BUILD_PLATFORM}