Optimization: get rid of triple run of isoinfo -d.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>

lib/vfs/mc-vfs/extfs/iso9660.in

@@ -23,12 +23,14 @@ test_iso () {
 	JOLIET_OPT="-J"
     fi
     ISOINFO="isoinfo -R"
-    isoinfo -d -i "$1" 2>/dev/null | @GREP@ "UCS level 1\|NO Joliet" > /dev/null || ISOINFO="$ISOINFO $JOLIET_OPT"
 
-    if [ `isoinfo -d -i "$1" 2>/dev/null | @GREP@ "Joliet with UCS level 3 found" | wc -l` == 1 ] ; then
-	if [ `isoinfo -d -i "$1" 2>/dev/null | @GREP@ "NO Rock Ridge" | wc -l` == 1 ] ; then
-	    SEMICOLON="YES"
-	fi
+    ISOINFO_D_I="`isoinfo -d -i "$1" 2>/dev/null`"
+
+    echo "$ISOINFO_D_I" | @GREP@ "UCS level 1\|NO Joliet" > /dev/null || ISOINFO="$ISOINFO $JOLIET_OPT"
+
+    if [ `echo "$ISOINFO_D_I" | @GREP@ "Joliet with UCS level 3 found" | wc -l` = 1 \
+        -a `echo "$ISOINFO_D_I" | @GREP@ "NO Rock Ridge" | wc -l` = 1 ] ; then
+        SEMICOLON="YES"
     fi
 }