[gcc/devel/rust/master] docker: Fix GCCRS_BUILD info

[Thomas Schwinge <tschwinge@gcc.gnu.org>]

https://gcc.gnu.org/g:ab0f9f9e1b9e55522e649d58520fdedcdb6c8859

commit ab0f9f9e1b9e55522e649d58520fdedcdb6c8859
Author: Arthur Cohen <arthur.cohen@embecosm.com>
Date:   Wed Jun 8 10:57:16 2022 +0200

    docker: Fix GCCRS_BUILD info
    
    Sometimes, the GCCRS_BUILD file would end up empty. I believe this is
    due to how Dockerfiles work in that there was a "race condition" between
    the two `RUN` commands. Hopefully this should fix it.

Diff:
---
 Dockerfile | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index da97edacb9e..759b934fc42 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -50,6 +50,7 @@ RUN apt-get update; \
 ADD . /usr/src/gcc
 RUN /bin/sh -c set -ex; \
     cd /usr/src/gcc; \
+    git log -1 --format="%h" > /GCCRS_BUILD; \
     ./contrib/download_prerequisites; 	{ rm *.tar.* || true; }; \
     mkdir -p /usr/src/gcc/gcc-build; \
     cd /usr/src/gcc/gcc-build; \
@@ -59,9 +60,6 @@ RUN /bin/sh -c set -ex; \
     cd /root; \
     rm -rf /usr/src/gcc
 
-RUN cd /usr/src/gcc; \
-  git log -1 --format="%h" > /GCCRS_BUILD; \
-
 RUN /bin/sh -c set -ex; \
     echo '/usr/local/lib64' > /etc/ld.so.conf.d/local-lib64.conf; \
     ldconfig -v