hammerhead: update max concurrent-instances limit.
hammerhead: update max concurrent-instances limit.

Bug: 22603171
Change-Id: I1bd6790d702377d8ab6e78c37fef1631c4e10b78

maruos/android_device_lge_hammerhead,maruos/android_device_lge_hammerhead,maruos/android_device_lge_hammerhead,maruos/android_device_lge_hammerhead