Add a patch, obtained from upstream, which fixes a bug with "wait -n pid"
if that wait is interrupted by a trapped signal.  A later wait for the
same pid would return status 127 (process not found) even though the
process was still running (and still in bash's jobs table).

This was a bug introduced in bash 5.1 (does not occur in 5.0 or earlier).

This patch should be removed when bash is next updated (to 5.2 or beyond)
(the change will be in the bash codebase) or if a patch is released from
upstream to fix this problem.

PGKREVISION++

{ This change is not significant enough to warrant an entry in doc/CHANGES. }

(kre)