anv/blit: Use CLAMP_TO_EDGE for scaled blits
anv/blit: Use CLAMP_TO_EDGE for scaled blits

When upscaling you can end up interpolating between the edge pixel and one
past the edge.  Using CLAMP_TO_EDGE seems like the most reasonable thing to
do in this case.  This fixes two of the new Vulkan CTS tests in
dEQP-VK.api.copy_and_blit.blit_image.*

Jason Ekstrand <jason@jlekstrand.net>
Reviewed-by: Ian Romanick <2b237cafb16dc45038e85df6c85e74e6d899eba9@intel.com>
Cc: "12.0" <59f39c0db42d4479a46b02d4d2bc11120e37bb44@lists.freedesktop.org>

metora/MesaGLSLCompiler,metora/MesaGLSLCompiler,metora/MesaGLSLCompiler