nak,nir: Add 32-bit nir_op_lea_nv and use it

Changes code size by -0.80% on shaderdb.

Reviewed-by: Faith Ekstrand <faith.ekstrand@collabora.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/32517>

src/compiler/nir/nir_opcodes.py

@@ -1412,6 +1412,11 @@ opcode("prmt_nv", 0, tuint32, [0, 0, 0], [tuint32, tuint32, tuint32],
         dst |= ((uint32_t)x) << i * 8;
     }""")
 
+# Address arithmetic instructions: shift and add
+# Shift must be a constant.
+opcode("lea_nv", 0, tuint32, [0, 0, 0], [tuint32, tuint32, tuint32], False,
+       "", "src0 + (src1 << (src2 % bit_size))")
+
 # 24b multiply into 32b result (with sign extension)
 binop("imul24", tint32, _2src_commutative + associative,
       "(((int32_t)src0 << 8) >> 8) * (((int32_t)src1 << 8) >> 8)")