fix memory leaking

There is a possible memory leaking when lo is allocated but
the lo->name is not. In this case, we should free the lo and then return

original change I475968bd570a113c9f61f02b974d57d1caaa0236

picked from: https://android-review.googlesource.com/#/c/23450/

as seen on: http://review.cyanogenmod.com/#/c/13782/

Change-Id: I21dd3267fa2521578d93f7b1a7bc2a6726de15ac
Merge branch 'jb-mr1-release' of https://android.googlesource.com/platform/external/dnsmasq into mr1-staging
Merge tag 'android-4.3_r2.1' into cm-10.2

Android 4.3 release 2.1
Merge remote-tracking branch 'cm/cm-10.2' into HEAD