panfrost: Don't initialise the trampolines array

PIPE_MAX_SHADER_SAMPLER_VIEWS is 128, so we just end up initialising a
kilobyte of memory for no reason, when usually only a couple of
sampler views are used.

Fixes: 53ef20f08d4 ("panfrost: Handle NULL sampler views")
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/15366>
1 file changed