data/scripts/backup: don't backup /var/log if it is not a directory

Origin commit data
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Branch: ni/coolstream
Commit: c3abfa581f
Author: vanhofen <vanhofen@gmx.de>
Date: 2023-10-05 (Thu, 05 Oct 2023)

Origin message was:
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- data/scripts/backup: don't backup /var/log if it is not a directory

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No further description and justification available within origin commit message!

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This commit was generated by Migit

data/scripts/backup_flash.sh.in

@@ -9,8 +9,7 @@ BAKF="/var/backup_flash.tar.gz"
 
 TOBACKUP=""
 
-SHOWINFO "backup to ${BAKF} ..."
-
+# add tobackup.conf and its content
 if [ -e "${USRF}" ]; then
 	TOBACKUP="$TOBACKUP ${USRF}"
 	while read i
@@ -18,6 +17,8 @@ if [ -e "${USRF}" ]; then
 		done < $USRF
 fi
 
+SHOWINFO "backup to ${BAKF} ..."
+
 # check existence and skip files in /var
 for i in $TOBACKUP; do
 	if [ -e "$i" -a ${i:0:${#VAR}} != ${VAR} ]; then