Travis: don't do APM2 build in travis any more

we no longer require APM2 compatibility for patches in master

Tools/scripts/build_all_travis.sh

@@ -12,21 +12,20 @@ set -x
 
 # If TRAVIS_BUILD_TARGET is not set, default to all of them
 if [ -z "$TRAVIS_BUILD_TARGET" ]; then
-    TRAVIS_BUILD_TARGET="sitl linux apm2 navio px4-v2"
+    TRAVIS_BUILD_TARGET="sitl linux navio px4-v2"
 fi
 
 declare -A build_platforms
 declare -A build_concurrency
 declare -A build_extra_clean
 
-build_platforms=(  ["ArduPlane"]="apm2 navio sitl linux px4-v2"
+build_platforms=(  ["ArduPlane"]="navio sitl linux px4-v2"
                    ["ArduCopter"]="navio sitl linux px4-v2"
-                   ["APMrover2"]="apm2 navio sitl linux px4-v2"
-                   ["AntennaTracker"]="apm2 navio sitl linux px4-v2"
+                   ["APMrover2"]="navio sitl linux px4-v2"
+                   ["AntennaTracker"]="navio sitl linux px4-v2"
                    ["Tools/Replay"]="linux")
 
-build_concurrency=(["apm2"]="-j2"
-                   ["navio"]="-j2"
+build_concurrency=(["navio"]="-j2"
                    ["sitl"]="-j2"
                    ["linux"]="-j2"
                    ["px4-v2"]="")