Tools: remove references to config.mk

dates from APM-build days.  The build server files references APM1 which is long gone.  Users running build_binaries can pollute their own environments, not need for this.

Tools/scripts/build_all.sh

@@ -3,8 +3,6 @@
 # This helps when doing large merges
 # Andrew Tridgell, November 2011
 
-. config.mk
-
 set -e
 set -x
 

Tools/scripts/build_autotest.sh

@@ -84,7 +84,6 @@ git reset --hard origin/master
 git pull || report_pull_failure
 git clean -f -f -x -d -d
 git tag autotest-$(date '+%Y-%m-%d-%H%M%S') -m "test tag `date`"
-cp ../config.mk .
 popd
 
 rsync -a APM/Tools/autotest/web-firmware/ buildlogs/binaries/

Tools/scripts/build_binaries.py

@@ -641,18 +641,6 @@ is bob we will attempt to checkout bob-AVR'''
                                  (str(self.tags)))
             self.dirty = True
 
-    def pollute_env_from_file(self, filepath):
-        with open(filepath) as f:
-            for line in f:
-                try:
-                    (name, value) = str.split(line, "=")
-                except ValueError as e:
-                    self.progress("%s: split failed: %s" % (filepath, str(e)))
-                    continue
-                value = value.rstrip()
-                self.progress("%s: %s=%s" % (filepath, name, value))
-                os.environ[name] = value
-
     def remove_tmpdir(self):
         if os.path.exists(self.tmpdir):
             self.progress("Removing (%s)" % (self.tmpdir,))
@@ -705,10 +693,6 @@ is bob we will attempt to checkout bob-AVR'''
         self.basedir = os.getcwd()
         self.error_strings = []
 
-        if os.path.exists("config.mk"):
-            # FIXME: narrow exception
-            self.pollute_env_from_file("config.mk")
-
         if not self.dirty:
             self.run_git_update_submodules()
         self.buildroot = os.path.join(os.environ.get("TMPDIR"),