rc: reorder_libs: [1/2] Drop unused _l, exit early on failure

[Klemens Nanni]

$_l is not used and picking the latest archive versions is of no use
if /usr/lib cannot be written to.

This patch applies cleanly before my next one but not vice versa.

Feedback? OK?

Index: rc
===================================================================
RCS file: /cvs/src/etc/rc,v
retrieving revision 1.507
diff -u -p -r1.507 rc
--- rc  4 Jul 2017 19:02:11 -0000       1.507
+++ rc  16 Jul 2017 01:25:27 -0000
@@ -158,7 +158,7 @@ make_keys() {
 
 # Re-link libraries, placing the objects in a random order.
 reorder_libs() {
-       local _dkdev _l _liba _libas _mp _tmpdir _remount=false _error=false
+       local _dkdev _liba _libas _mp _tmpdir _remount=false _error=false
 
        [[ $library_aslr == NO ]] && return
 
@@ -168,6 +168,16 @@ reorder_libs() {
        # Skip if /usr/lib is on a nfs mounted filesystem.
        [[ $_mp == *' type nfs '* ]] && return
 
+       # Remount read-write, if /usr/lib is on a read-only ffs filesystem.
+       if [[ $_mp == *' type ffs '*'read-only'* ]]; then
+               if mount -u -w $_dkdev; then
+                       _remount=true
+               else
+                       echo ' failed.'
+                       return
+               fi
+       fi
+
        echo -n 'reordering libraries:'
 
        # Only choose the latest version of the libraries.
@@ -178,16 +188,6 @@ reorder_libs() {
                done
                _libas="$_libas $_liba"
        done
-
-       # Remount read-write, if /usr/lib is on a read-only ffs filesystem.
-       if [[ $_mp == *' type ffs '*'read-only'* ]]; then
-               if mount -u -w $_dkdev; then
-                       _remount=true
-               else
-                       echo ' failed.'
-                       return
-               fi
-       fi
 
        for _liba in $_libas; do
                _tmpdir=$(mktemp -dq /tmp/_librebuild.XXXXXXXXXXXX) && (