filesystem: mount rw /media with fstab

/media will be a tmpfs.
This is done so that /media is writeable in a
read-only filesystem to be able to mount the
ubi volumes for the systems that implement the
software interfaces.

Resolves openbmc/openbmc#2072

Change-Id: Id6163fe43843f9d17ef49760dee1caee7cc17ceb
Signed-off-by: Leonel Gonzalez <lgonzalez@us.ibm.com>
diff --git a/common/recipes-core/base-files/base-files/fstab b/common/recipes-core/base-files/base-files/fstab
index eab105b..45784b4 100644
--- a/common/recipes-core/base-files/base-files/fstab
+++ b/common/recipes-core/base-files/base-files/fstab
@@ -7,3 +7,4 @@
 ubi0:rwfs            /var                 ubifs      defaults              0  0
 overlay              /etc                 overlay    defaults,x-systemd.requires=prepare-overlay.service,lowerdir=/etc,upperdir=/var/persist/etc,workdir=/var/persist/etc-work 0  0
 tmpfs                /var/volatile        tmpfs      defaults              0  0
+tmpfs                /media               tmpfs      defaults              0  0