Fix a issue with multi-value sysctls
Fix a issue with multi-value sysctls

Following state file to reproduce:

    net.ipv4.tcp_rmem:
      sysctl:
        - present
        - value: 4096 87380 16777216

    net.ipv4.tcp_wmem:
      sysctl:
        - present
        - value: 4096 87380 16777216

Without this patch, these two sysctls will be constantly
set over and over again each time state.highstate is called

saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt,saltstack/salt