Unlike image views, buffer views don't have a component mapping field,
so we were setting the mapping to identity swizzles for uniform texel
buffers. However, we also use the component mapping for assigning 0 or 1
to components not provided by the texel format:
https://swiftshader-review.googlesource.com/c/SwiftShader/+/31388

This change ensures we still get the 0 and 1 in the desired channels for
uniform texel buffers.

Bug: b/168052622
Test: dEQP-VK.texture.texel_buffer.uniform.packed.b10g11r11-ufloat-pack32
Change-Id: I40885f998a53e371e1e2358ed197fc3446916d8c
Reviewed-on: https://swiftshader-review.googlesource.com/c/SwiftShader/+/48268Tested-by: Nicolas Capens <nicolascapens@google.com>
Kokoro-Result: kokoro <noreply+kokoro@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>