Unify PPC Dockerfiles

Author: mati865

ci/docker/powerpc-unknown-linux-gnu/Dockerfile

@@ -3,10 +3,9 @@ FROM ubuntu:18.04
 RUN apt-get update && apt-get install -y --no-install-recommends \
         gcc libc6-dev qemu-user ca-certificates \
         gcc-powerpc-linux-gnu libc6-dev-powerpc-cross \
-        qemu-system-ppc \
-        make \
-        file
+        qemu-system-ppc make file
 
 ENV CARGO_TARGET_POWERPC_UNKNOWN_LINUX_GNU_LINKER=powerpc-linux-gnu-gcc \
     CARGO_TARGET_POWERPC_UNKNOWN_LINUX_GNU_RUNNER="qemu-ppc -cpu Vger -L /usr/powerpc-linux-gnu" \
+    CC=powerpc-linux-gnu-gcc \
     OBJDUMP=powerpc-linux-gnu-objdump

ci/docker/powerpc64-unknown-linux-gnu/Dockerfile

@@ -1,15 +1,9 @@
 FROM ubuntu:18.04
 
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    gcc \
-    ca-certificates \
-    libc6-dev \
-    gcc-powerpc64-linux-gnu \
-    libc6-dev-ppc64-cross \
-    qemu-user  \
-    qemu-system-ppc \
-    make \
-    file 
+        gcc libc6-dev qemu-user ca-certificates \
+        gcc-powerpc64-linux-gnu libc6-dev-ppc64-cross \
+        qemu-system-ppc file make
 
 ENV CARGO_TARGET_POWERPC64_UNKNOWN_LINUX_GNU_LINKER=powerpc64-linux-gnu-gcc \
     CARGO_TARGET_POWERPC64_UNKNOWN_LINUX_GNU_RUNNER="qemu-ppc64 -L /usr/powerpc64-linux-gnu" \