scripts: Move deploy_chrome's default mount dir to /usr/local/

As requested in https://crbug.com/1212649. Seems the old mount dir
(/mnt/stateful_partition/deploy_rootfs) should have different mount
settings that the chrome binary wouldn't like sitting on.

So this moves it to /usr/local/, which appears to be where all tests'
working dirs go.

BUG=chromium:1212649
TEST=unittests
TEST=ran this on chrome's simple chrome bots: crrev.com/c/2967505/33

Change-Id: Ibcc231013cc21c131dee20df7667db43fda72c80
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/chromite/+/4350412
Tested-by: Ben Pastene <bpastene@chromium.org>
Reviewed-by: Achuith Bhandarkar <achuith@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Ben Pastene <bpastene@chromium.org>
diff --git a/scripts/deploy_chrome.py b/scripts/deploy_chrome.py
index d6d5960..c8753ce 100644
--- a/scripts/deploy_chrome.py
+++ b/scripts/deploy_chrome.py
@@ -61,7 +61,7 @@
 _ANDROID_DIR_EXTRACT_PATH = "system/chrome/*"
 
 _CHROME_DIR = "/opt/google/chrome"
-_CHROME_DIR_MOUNT = "/mnt/stateful_partition/deploy_rootfs/opt/google/chrome"
+_CHROME_DIR_MOUNT = "/usr/local/opt/google/chrome"
 _CHROME_DIR_STAGING_TARBALL_ZSTD = "chrome.tar.zst"
 _CHROME_TEST_BIN_DIR = "/usr/local/libexec/chrome-binary-tests"