nir/algebraic: Replace the big switch with a table

Now that we're using meaningless state indices instead of opcodes, let's
just put them all in a table and avoid the switch statement. Surprisingly,
this actually makes the binary a bit larger but avoiding the switch
might improve perf a bit.

Before this change:

       text	   data	    bss	    dec	    hex	filename
    5517205	 481040	 106936	6105181	 5d285d	_install/lib64/libvulkan_intel.so

After this change:

       text	   data	    bss	    dec	    hex	filename
    5546301	 565200	 106936	6218437	 5ee2c5	_install/lib64/libvulkan_intel.so
14 jobs for !791 with review/nir-search-xform-table in 50 minutes and 39 seconds (queued for 16 seconds)
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meson-clang

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meson-gallium-clover-llvm

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meson-gallium-clover-llvm39

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meson-gallium-drivers-other

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meson-loader-classic-dri

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scons-llvm

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scons-nollvm

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