enter_chroot: drop netrc support

We use gitcookies everywhere now, so stop trying to copy this file in.
The logic for importing gitcookies has long existed here, so nothing
else needs to be done.

BUG=chromium:1024979
TEST=CQ passes

Change-Id: Iffe0da094c9bbf66ab172d607504e9ae997a5fea
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/1918112
Reviewed-by: Sean Abraham <seanabraham@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
diff --git a/sdk_lib/enter_chroot.sh b/sdk_lib/enter_chroot.sh
index 9796402..c32f7a9 100755
--- a/sdk_lib/enter_chroot.sh
+++ b/sdk_lib/enter_chroot.sh
@@ -82,7 +82,6 @@
   .gdata_cred.txt             # User/password for Google Docs on chromium.org
   .gdata_token                # Auth token for Google Docs on chromium.org
   .disable_build_stats_upload # Presence of file disables command stats upload
-  .netrc                      # May contain required source fetching credentials
   .inputrc                    # Preserve command line customizations
 )