[BugFix] explicitly setting the tensor shape of otp output (#3027)

When MTP and oprojTP are enabled, it triggers the recompilation of the
torchair graph, leading to a decrease in performance, and this PR fixes
this issue.

- vLLM version: v0.10.2
- vLLM main:
486c5599e3

---------

Signed-off-by: zzhx1 <zzh_201018@outlook.com>

vllm_ascend/ops/linear_op.py

@@ -299,6 +299,7 @@ class OProjRowParallelOp(CustomRowParallelOp):
 
         # otp-specific: Combine partial results across devices
         output = self.comm_group.reduce_scatter(output_parallel, dim=0)
+        output = output.view(input_.shape[0], self.layer.output_size)
 
         # Handle bias return based on configuration
         output_bias = self.bias if self.skip_bias_add else None