fix: iterate individual resblock hooks instead of parent container hooks

[Mr-Neutr0n]

Summary

• Fixed a copy-paste bug in GeneratorNSF.__prepare_scriptable__() in infer/lib/infer_pack/models.py (line 586)
• The for l in self.resblocks: loop was iterating over self.resblocks._forward_pre_hooks (the parent nn.ModuleList container's hooks) instead of l._forward_pre_hooks (each individual resblock's hooks)
• This meant weight norm hooks on individual resblocks were never found and never removed during script preparation, while the container's hooks (which typically has none) were checked repeatedly

Details

The identical pattern appears correctly in two other places in the same file:

• Generator.__prepare_scriptable__() (line 297) — correctly uses l._forward_pre_hooks
• GeneratorNSF.__prepare_scriptable__() for self.ups (line 575) — correctly uses l._forward_pre_hooks

Only the self.resblocks loop in GeneratorNSF.__prepare_scriptable__() had this bug.

Test plan

• Verify GeneratorNSF.__prepare_scriptable__() correctly removes weight norm from individual resblocks when preparing for TorchScript
• Confirm no regression in model inference after the fix