ui: Do not shadow '_' where it's used as a literal syntax match.
Fixes compilation with Guile 2.1.
Reported by Mu Lei.
* guix/ui.scm (report-load-error)
(warn-about-load-error, read/eval-package-expression): Use 'rest'
instead of '_' as the pattern variable name.
* gnu/packages.scm (%find-package): Likewise.
* guix/scripts/build.scm (transform-package-inputs): Likewise.
* guix/scripts/hash.scm (guix-hash): Likewise.
* guix/scripts/import/gnu.scm (%options, guix-import-gnu): Likewise.
* guix/scripts/import/nix.scm (guix-import-nix): Likewise.
* guix/scripts/offload.scm (build-machines): Likewise.
* guix/scripts/refresh.scm (%options): Likewise.
* guix/scripts/substitute.scm (narinfo-signature->canonical-sexp):
Likewise.
e465d9e190