Fix sizes and buffer names passed to deMemset corresponding to the buffers

Fix sizes and buffer names passed to deMemset corresponding to the buffers

Corrected deMemset size parameter for indexBufferMonolithicData from size of
ValueBuffer to size of uint32_t. Size correction also made for
valuesBufferMonolithicData from size of uint32_t to size of ValueBuffer.
Added missing deMemset for valuesBufferGPLData.

Affects:
dEQP-VK.pipeline.fast_linked_library.misc.interpolate_at_sample_no_sample_shading

Components: Vulkan
VK-GL-CTS issue: 4328

Change-Id: Id0b4a17167bba7c06bdbe293d99c1ce2dbf2223f