CANN: remove custom error limit for SSM_CONV

Author: 0Marble

tests/test-backend-ops.cpp

@@ -3379,14 +3379,6 @@ struct test_ssm_conv : public test_case {
         ggml_tensor * out = ggml_ssm_conv(ctx, a, b);
         return out;
     }
-
-    // for CANN Ascend310P3:
-    // this card requires setting cubeMathType=1 (ALLOW_FP32_DOWN_PRECISION)
-    // so the inputs are converted from f32
-    // and tests fail with NMSE = 0.000000114 > 0.000000100
-    double max_nmse_err() override {
-        return 1e-6;
-    }
 };
 
 // GGML_OP_SSM_SCAN