[skolo] Let Macs find the mounted volumes by default.

Change-Id: Ia2bf1a17c7f7fc0303aebfcafead17ace066746e
Reviewed-on: https://skia-review.googlesource.com/c/buildbot/+/598786
Commit-Queue: Joe Gregorio <jcgregorio@google.com>
Auto-Submit: Erik Rose <erikrose@google.com>
Reviewed-by: Joe Gregorio <jcgregorio@google.com>
diff --git a/skolo/raspberry-pi/configure-image.sh b/skolo/raspberry-pi/configure-image.sh
index 4cc4868..7828687 100755
--- a/skolo/raspberry-pi/configure-image.sh
+++ b/skolo/raspberry-pi/configure-image.sh
@@ -8,7 +8,11 @@
 # Record the directory of this file.
 REL=$(dirname "$0")
 
-DEFAULT_MOUNT=/media/${USER}/RASPIROOT
+if [ "$(uname -s)" = Darwin ]; then
+    DEFAULT_MOUNT=/Volumes/RASPIROOT
+else
+    DEFAULT_MOUNT=/media/${USER}/RASPIROOT
+fi
 
 # Check argument count is valid.
 if [ $# == 0 ]; then