intel/disasm/gfx12+: Use helper instead of hardcoded bit access for 64-bit immediates.

So we don't have to duplicate code to handle differences in the
encoding of 64-bit immediates across platforms.

Reviewed-by: Lionel Landwerlin <lionel.g.landwerlin@intel.com>
Part-of: <https://gitlab.freedesktop.org/mesa/mesa/-/merge_requests/20543>

src/intel/compiler/brw_disasm.c

@@ -1548,7 +1548,7 @@ imm(FILE *file, const struct brw_isa_info *isa, enum brw_reg_type type,
       }
       break;
    case BRW_REGISTER_TYPE_DF:
-      format(file, "0x%016"PRIx64"DF", brw_inst_bits(inst, 127, 64));
+      format(file, "0x%016"PRIx64"DF", brw_inst_imm_uq(devinfo, inst));
       pad(file, 48);
       format(file, "/* %-gDF */", brw_inst_imm_df(devinfo, inst));
       break;