NdcDispatcher - fix bugprone-suspicous-string-compare warnings

Fixes:
  system/netd/server/NdcDispatcher.cpp:989:20: warning: function strcmp is called without explicitly comparing result [bugprone-suspicious-string-compare]
  system/netd/server/NdcDispatcher.cpp:1109:20: ...
  system/netd/server/NdcDispatcher.cpp:1136:20: ...

Test: builds
Bug: 153035880
Signed-off-by: Maciej Żenczykowski <maze@google.com>
Change-Id: I48056fa81af823f14d2f41885bd1a824e1d5ddd2
1 file changed