fbarray: fix log message on truncation error

fbarray: fix log message on truncation error

When file truncation fails, the log message attempts to print a path of
file we failed to truncate, but this path was never set to anything and,
what's worse, was uninitialized. Fix it by passing path from the caller.

Coverity issue: 366122
Fixes: c44d09811b40 ("eal: add shared indexed file-backed array")
Cc: stable@dpdk.org
Reported-by: Andrew Boyer <aboyer@pensando.io>
Signed-off-by: Anatoly Burakov <anatoly.burakov@intel.com>
Reviewed-by: David Marchand <david.marchand@redhat.com>