all: format code according to Go 1.19 rules

Go 1.19 started reformatting code in a way that makes it more obvious
how it will be rendered on pkg.go.dev. It gets it almost right, but not
entirely. Therefore, I had to modify some of the comments so that they
are formatted correctly.

src/runtime/runtime_tinygowasm.go

@@ -19,6 +19,7 @@ func fd_write(id uint32, iovs *__wasi_iovec_t, iovs_len uint, nwritten *uint) (e
 
 // See:
 // https://github.com/WebAssembly/WASI/blob/main/phases/snapshot/docs.md#-proc_exitrval-exitcode
+//
 //go:wasm-module wasi_snapshot_preview1
 //export proc_exit
 func proc_exit(exitcode uint32)