anv: Increase state allocation size limit to 2MB

When running on ICL the
dEQP-VK.ssbo.phys.layout.random.16bit.scalar.13 needs more than 1M for
the shader, so bump it.
10 jobs for !1333 with r/anv-bucket-size in 9 minutes and 40 seconds (queued for 2 seconds)
detached
Status Job ID Name Coverage
  Containers Build
passed #418908
debian

00:00:18

 
  Build+Test
passed #418910
meson-clang

00:07:59

passed #418914
meson-clover

00:07:16

passed #418913
meson-main

00:05:14

passed #418909
meson-swr-glvnd

00:03:10

passed #418915
meson-vulkan

00:02:57

passed #418917
scons-llvm

00:06:22

passed #418916
scons-nollvm

00:03:53

passed #418911
scons-swr

00:05:34

passed #418912
scons-win64

00:06:02