installer: Use system-wide guix for system init.

* gnu/installer.scm (installer-program): Remove dependency on the guix
package for the PATH.
* gnu/installer/final.scm (install-system): Set PATH inside container
to /run/current-system/profile/bin/.

Signed-off-by: Mathieu Othacehe <othacehe@gnu.org>

gnu/installer.scm

@@ -335,7 +335,6 @@ selected keymap."
                        ntfs-3g ;mkfs.ntfs
                        xfsprogs ;mkfs.xfs
                        kbd ;chvt
-                       guix ;guix system init call
                        util-linux ;mkwap
                        nano
                        shadow

gnu/installer/final.scm

@@ -170,8 +170,7 @@ or #f.  Return #t on success and #f on failure."
          (database-dir    "/var/guix/db")
          (database-file   (string-append database-dir "/db.sqlite"))
          (saved-database  (string-append database-dir "/db.save"))
-         (ret             #f)
-         (path (getenv "PATH")))
+         (ret             #f))
     (mkdir-p (%installer-target-dir))
 
     ;; We want to initialize user passwords but we don't want to store them in
@@ -210,7 +209,7 @@ or #f.  Return #t on success and #f on failure."
              (setvbuf (current-output-port) 'none)
              (setvbuf (current-error-port) 'none)
 
-             (setenv "PATH" path)
+             (setenv "PATH" "/run/current-system/profile/bin/")
 
              (set! ret (run-command install-command)))
            (lambda ()