vulkan: Temporarily hack around loader/driver mismatch

A driver was built with an older declaration of
vkGetSwapchainGrallocUsage2KHR, and doesn't match what libvulkan
expects. This is a temporary workaround until the driver can be
rebuilt against the current header. When a new driver is available,
this change should be reverted.

Test: vulkanGears on affected device
Change-Id: I5a8bb16f0f9563e32314cff2a2a7a45760cfc356