Fix depot_tools\git.bat when depot_tools in not in PATH.

Manual land of https://chromiumcodereview.appspot.com/2009173002/ due to CQ
lineending issues.

AUTHOR=techtonik@gmail.com
R=phajdan.jr@chromium.org, techtonik@gmail.com, dpranke@chromium.org
BUG=

Review URL: https://codereview.chromium.org/2015673002 .

git-svn-id: svn://svn.chromium.org/chrome/trunk/tools/depot_tools@300668 0039d316-1c4b-4281-b951-d872f2087c98

bootstrap/win/git.template.bat

 @echo off
 setlocal
 if not defined EDITOR set EDITOR=notepad
-set PATH=%~dp0GIT_BIN_DIR\cmd;%PATH%
+set PATH=%~dp0GIT_BIN_DIR\cmd;%~dp0;%PATH%
 "%~dp0GIT_BIN_DIR\GIT_PROGRAM" %*