Use mirror for BCC toolchain (#541)

* Update patchmaker dockerstub to use mirror server for downloading the BCC toolchain

* Update CHANGELOG.md

* Update CHANGELOG.md

Author: paulnoalhyt

ofrak_patch_maker/CHANGELOG.md

@@ -18,7 +18,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/)
 ### Changed
 - Removed `SUBALIGN(0)` for `.bss` sections
 - Minor update to OFRAK Community License, add OFRAK Pro License ([#478](https://github.com/redballoonsecurity/ofrak/pull/478))
-- Install toolchains from source or tarball instead of relying on the Debian package manager ([#502](https://github.com/redballoonsecurity/ofrak/pull/502))
+- Install toolchains from source or tarball instead of relying on the Debian package manager ([#502](https://github.com/redballoonsecurity/ofrak/pull/502), [#541](https://github.com/redballoonsecurity/ofrak/pull/541))
 
 ## [4.0.2](https://github.com/redballoonsecurity/ofrak/compare/ofrak-patch-maker-v.4.0.1...ofrak-patch-maker-v.4.0.2)
 ### Fixed

ofrak_patch_maker/Dockerstub

@@ -129,7 +129,7 @@ fi;
 #BCC (GCC) SPARC v8
 RUN if [ "$TARGETARCH" = "amd64" ]; then \
     cd /tmp/ \
-      && wget https://www.gaisler.com/anonftp/bcc2/bin/bcc-2.0.7-gcc-linux64.tar.xz --show-progress --progress=bar:force:noscroll \
+      && wget http://mirror.tensorflow.org/www.gaisler.com/anonftp/bcc2/bin/bcc-2.0.7-gcc-linux64.tar.xz --show-progress --progress=bar:force:noscroll \
       && mkdir -p /opt/rbs/toolchain/ \
       && tar -C /opt/rbs/toolchain/ -xJf bcc-2.0.7-gcc-linux64.tar.xz \
       && rm bcc-2.0.7-gcc-linux64.tar.xz; \