add phony target "all_modules" and use it as make goal for "mm"/"mmm"

So that mm/mmm don't depend on phony target "files", which brings in
unwanted files for apps-only build.
Also allow "dist" for mmm.
Bug: http://b/issue?id=2811503

Change-Id: I2c0794aebd1d171d8a0f44eb8cda67855704d6bd
diff --git a/envsetup.sh b/envsetup.sh
index 21a66c1..4d5bbc3 100644
--- a/envsetup.sh
+++ b/envsetup.sh
@@ -636,7 +636,7 @@
         elif [ ! "$M" ]; then
             echo "Couldn't locate a makefile from the current directory."
         else
-            ONE_SHOT_MAKEFILE=$M make -C $T files $@
+            ONE_SHOT_MAKEFILE=$M make -C $T all_modules $@
         fi
     fi
 }
@@ -668,13 +668,15 @@
                     ARGS="$ARGS snod"
                 elif [ "$DIR" = showcommands ]; then
                     ARGS="$ARGS showcommands"
+                elif [ "$DIR" = dist ]; then
+                    ARGS="$ARGS dist"
                 else
                     echo "No Android.mk in $DIR."
                     return 1
                 fi
             fi
         done
-        ONE_SHOT_MAKEFILE="$MAKEFILE" make -C $T $DASH_ARGS files $ARGS
+        ONE_SHOT_MAKEFILE="$MAKEFILE" make -C $T $DASH_ARGS all_modules $ARGS
     else
         echo "Couldn't locate the top of the tree.  Try setting TOP."
     fi