Fix issue #1842; fix some typos.

[ceri]

Not 100% that this is correct, but nrit is null when it gets called here so I think it is probably a typo.

Fixes #1842 , probably

[bapt]

Sorry it takes time on this one, I haven't have been able to fully review yet, maybe @vstakhov you have an opinion on this one?

[daniel-nebdal]

Hi. It's been a while since the last update, so I hope it's ok to bump this? It still seems to be a problem, and the patch still looks relevant:

> pkg --version
1.17.5
> gdb102 pkg
GNU gdb (GDB) 10.2 [GDB v10.2 for FreeBSD]
(...)
Reading symbols from pkg...
Reading symbols from /usr/lib/debug//usr/sbin/pkg.debug...
(gdb) run upgrade --yes --vulnerable
Starting program: /usr/sbin/pkg upgrade --yes --vulnerable
process 78447 is executing new program: /usr/local/sbin/pkg
Updating FreeBSD repository catalogue...
FreeBSD repository is up to date.
Updating Synth repository catalogue...
Synth repository is up to date.
All repositories are up to date.
vulnxml file up-to-date
[Detaching after fork from child process 78449]
Updating database digests format: 100%

Program received signal SIGSEGV, Segmentation fault.
0x0000000000517403 in pkg_jobs_process_remote_pkg (j=0x41015a2280, rp=0x4101417400, req=0x0, with_version=0) at pkg_jobs.c:782
782                             while (pkg_rdeps(nrit->pkg, &rdep) == EPKG_OK) {
(gdb) p nrit
$1 = (struct pkg_job_request_item *) 0x0
(gdb) p nit
$2 = (struct pkg_job_universe_item *) 0x4101411700
(gdb)