Reduce advertised sys mem on 32 bit Android

Reduce advertised sys mem on 32 bit Android

This CL reduces the advertised system memory amount in 32 bit Android
builds to address some memory fragmentation issues in certain tests
that rely on the advertised memory amount.

Affects:

dEQP-VK.api.buffer.suballocation.*
dEQP-VK.api.buffer.dedicated_alloc.*
dEQP-VK.api.object_management.*
dEQP-VK.memory.allocation.*
dEQP-VK.memory.device_group_allocation.*
dEQP-VK.pipeline.render_to_image.*.small.*
dEQP-VK.pipeline.render_to_image.*.huge.*

Components: Framework, Vulkan

VK-GL-CTS issue: 3586

Change-Id: I15ef027e3f69ddbb87e8704d0cff479782b6bda6