guix: Add codesigning functionality

contrib/guix/guix-build

@@ -267,20 +267,20 @@ for host in $HOSTS; do
     make -C "${PWD}/depends" -j"$JOBS" download-"$(host_to_commonname "$host")" ${V:+V=1} ${SOURCES_PATH:+SOURCES_PATH="$SOURCES_PATH"}
 done
 
-# Usage: outdir_for_host HOST
+# Usage: outdir_for_host HOST SUFFIX
 #
 #   HOST: The current platform triple we're building for
 #
 outdir_for_host() {
-    echo "${OUTDIR_BASE}/${1}"
+    echo "${OUTDIR_BASE}/${1}${2:+-${2}}"
 }
 
-# Usage: profiledir_for_host HOST COMMAND
+# Usage: profiledir_for_host HOST SUFFIX
 #
 #   HOST: The current platform triple we're building for
 #
 profiledir_for_host() {
-    echo "${PROFILES_BASE}/${2}-${1}"
+    echo "${PROFILES_BASE}/${1}${2:+-${2}}"
 }
 
 
@@ -412,7 +412,7 @@ EOF
                                  --keep-failed \
                                  --fallback \
                                  --link-profile \
-                                 --root="$(profiledir_for_host "${HOST}" build)" \
+                                 --root="$(profiledir_for_host "${HOST}")" \
                                  ${SUBSTITUTE_URLS:+--substitute-urls="$SUBSTITUTE_URLS"} \
                                  ${ADDITIONAL_GUIX_COMMON_FLAGS} ${ADDITIONAL_GUIX_ENVIRONMENT_FLAGS} \
                                  -- env HOST="$host" \