Set max number of allowed users for cuttlefish. Bug: 119619197 Test: build and run Change-Id: I51f757273390906f065f864bd5878f42ad591b4b (cherry picked from commit 72bf5abe1f86e0c7762847657d4c7231e5ced715) (cherry picked from commit a50743734028bf438953c600cd0af4412d270c72)