CI revealed one:
```
cc plugins/libplugin-pay.c
plugins/libplugin-pay.c: In function ‘payment_getroute’:
plugins/libplugin-pay.c:888:17: error: ‘errstr’ may be used uninitialized [-Werror=maybe-uninitialized]
888 | payment_fail(p, "%s", errstr);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
plugins/libplugin-pay.c:851:21: note: ‘errstr’ was declared here
851 | const char *errstr;
| ^~~~~~
cc1: all warnings being treated as errors
```
My local compiler gave another:
```
channeld/channeld.c: In function ‘resume_splice_negotiation’:
channeld/channeld.c:3734:23: error: ‘final_tx’ may be used uninitialized [-Werror=maybe-uninitialized]
3734 | msg = towire_channeld_splice_confirmed_signed(tmpctx, final_tx,
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
3735 | chan_output_index);
| ~~~~~~~~~~~~~~~~~~
channeld/channeld.c:3461:28: note: ‘final_tx’ was declared here
3461 | struct bitcoin_tx *final_tx;
| ^~~~~~~~
cc1: all warnings being treated as errors
make: *** [Makefile:298: channeld/channeld.o] Error 1
```
So fix both.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
a12e41a930