transform: restore previous test behavior

I think it's much nicer to have the test output inline in the source
file, that way it's much easier to review any changes. For example, when
escape analysis is improved this is visible with removed `// OUT` lines.

This is similar to how LLVM writes its tests, and I like that style.

transform/testdata/allocs2.out.cover

@@ -1,11 +1,11 @@
-testdata/allocs2.go:24.1,24.43 1 0
-testdata/allocs2.go:26.1,26.25 1 0
-testdata/allocs2.go:29.1,29.22 1 0
-testdata/allocs2.go:36.1,36.23 1 0
-testdata/allocs2.go:44.1,44.23 1 0
-testdata/allocs2.go:46.1,46.22 1 0
-testdata/allocs2.go:49.1,49.9 1 0
-testdata/allocs2.go:50.1,50.9 1 0
-testdata/allocs2.go:107.1,107.21 1 0
-testdata/allocs2.go:114.1,114.23 1 0
-testdata/allocs2.go:128.1,128.23 1 0
+testdata/allocs2.go:24.1,24.72 1 0
+testdata/allocs2.go:26.1,26.91 1 0
+testdata/allocs2.go:29.1,29.49 1 0
+testdata/allocs2.go:36.1,36.50 1 0
+testdata/allocs2.go:44.1,44.50 1 0
+testdata/allocs2.go:46.1,46.49 1 0
+testdata/allocs2.go:49.1,49.36 1 0
+testdata/allocs2.go:50.1,50.36 1 0
+testdata/allocs2.go:107.1,107.49 1 0
+testdata/allocs2.go:114.1,114.51 1 0
+testdata/allocs2.go:128.1,128.55 1 0