enter_chroot.sh: Downgrade "mounting local folders" log message to debug

If a user has a `.local_mounts` configuration present, then each time
`cros_sdk` is called the log message "Mounting local folders" will be
displayed on screen. This log message can be a little noisy for users
constantly entering/exiting the chroot.

Update the log message to print only at the debug log-level, matching
other similar log statements in the file.

BUG=None
TEST=Run `cros_sdk` with a `.local_mounts` configuration present.

Change-Id: I67b485d2889eb2f73dd5f953de24fcd03e9261dc
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/3353559
Reviewed-by: Sergey Frolov <sfrolov@google.com>
Tested-by: David Greenaway <dgreenaway@google.com>
Auto-Submit: David Greenaway <dgreenaway@google.com>
Commit-Queue: David Greenaway <dgreenaway@google.com>
diff --git a/sdk_lib/enter_chroot.sh b/sdk_lib/enter_chroot.sh
index 21d0fc7..a1af4b2 100755
--- a/sdk_lib/enter_chroot.sh
+++ b/sdk_lib/enter_chroot.sh
@@ -569,7 +569,7 @@
     # Mount additional directories as specified in .local_mounts file.
     local local_mounts="${FLAGS_trunk}/src/scripts/.local_mounts"
     if [[ -f ${local_mounts} ]]; then
-      info "Mounting local folders"
+      debug "Mounting local folders"
       # format: mount_source
       #      or mount_source mount_point
       #      or # comments