cros_show_stacks: Fix when path to dump contains spaces

BUG=None
TEST=./cros_show_stacks --board=$BOARD '/path to/dump.dmp'

Change-Id: Icea562eb2cb7c327d02b171d3f905d1f8f6d6885
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crosutils/+/2757820
Tested-by: Shao-Chuan Lee <shaochuan@chromium.org>
Reviewed-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Shao-Chuan Lee <shaochuan@chromium.org>
1 file changed