Resolve add linux as cross-compilation platform

.dockerignore

@@ -0,0 +1 @@
+/target

docker/Dockerfile.x86_64-pc-windows-gnu

@@ -1,11 +1,7 @@
-FROM rustembedded/cross:x86_64-pc-windows-gnu
+FROM docker.io/rustembedded/cross:x86_64-pc-windows-gnu
 
 RUN dpkg --add-architecture i386 && apt-get update && \
     apt-get install --assume-yes --no-install-recommends \
-    wine-stable \
-    wine64 \
-    wine32 \
-    libz-mingw-w64-dev \
     llvm-dev \
     libclang-dev \
     clang

docker/Dockerfile.x86_64-unknown-linux-gnu

@@ -1,7 +1,10 @@
-FROM rustembedded/cross:x86_64-unknown-linux-gnu
+FROM docker.io/rustembedded/cross:x86_64-unknown-linux-gnu
 
 RUN yum update -y && \
     yum install centos-release-scl -y && \
-    yum install llvm-toolset-7 -y && \
-    yum install scl-utils -y && \
-    echo "source scl_source enable llvm-toolset-7" >> ~/.bash_profile
+    yum install llvm-toolset-7 -y
+
+COPY docker/scl_enable /usr/bin/scl_enable
+ENV BASH_ENV="/usr/bin/scl_enable" \
+    ENV="/usr/bin/scl_enable" \
+    PROMPT_COMMAND=". /usr/bin/scl_enable"

docker/scl_enable

@@ -0,0 +1,2 @@
+unset BASH_ENV PROMPT_COMMAND ENV
+source scl_source enable llvm-toolset-7