recovery-initramfs-init: fix psplash communication FIFO path

The latest version of psplash changed the default path to store the
communication FIFO with other processes to "/run" to allow keeping the
information between reboots, however we are using this tool from an initramfs
where "/run" does not exist, producing multiple errors trying to write to a
nonexistent path, delaying the update process.

This commit forces psplash to use an existing path like "/tmp" to handle the
communication FIFO, because we don't need to maintain the update information.

https://onedigi.atlassian.net/browse/CC8X-318

Signed-off-by: Arturo Buzarra <arturo.buzarra@digi.com>

meta-digi-dey/recipes-core/recovery/recovery-initramfs/recovery-initramfs-init

@@ -520,6 +520,9 @@ mkdir -p /var/lock
 # Set kernel console loglevel.
 sysctl -q -w kernel.printk=4
 
+# Set path for psplash communication FIFO
+export PSPLASH_FIFO_DIR="/tmp"
+
 # Start psplash.
 psplash &