Replaced "source ..." with ". ..." because ash doesn't know "source"

initrd_hooks/lipnsa.hook.sh

@@ -7,7 +7,7 @@ LOGFUNCTIONSSOURCE="/scripts/casper-functions"
 TARGET="/root"
 
 if [ -e "${LOGFUNCTIONSSOURCE}" ]; then
-  source ${LOGFUNCTIONSSOURCE}
+  . ${LOGFUNCTIONSSOURCE}
 else
   echo "Warning: ${LOGFUNCTIONSSOURCE} does not exist. Cannot source casper functions!"
 fi