Report missing directory if we can not initialise alpm library

When pacman failed to initialise the alpm library due to the database
directory being missing (either via the root not existing or the database
directory itself not existing), it just printed the non-informative
message "could not find or read directory".  Add the directory
information the the error output.  E.g.:

error: failed to initialize alpm library
(could not find or read directory: /this/does/not/exist/var/lib/pacman/)

Signed-off-by: Allan McRae <allan@archlinux.org>

0 files changed, 0 insertions, 0 deletions