* find/exec.c: New file.
(initialise_wd_for_exec): Move out of pred.c
(record_exec_dir): Likewise.
(impl_pred_exec): Likewise.
(prep_child_for_exec): Likewise.
(launch): Likewise.
* find/pred.c: These functions are moved out of this file.
* find/defs.h: impl_pred_exec is no longer static in pred.c,
* find/exec.c: New file.
(initialise_wd_for_exec): Move out of pred.c
(record_exec_dir): Likewise.
(impl_pred_exec): Likewise.
(prep_child_for_exec): Likewise.
(launch): Likewise.
* find/pred.c: These functions are moved out of this file.
* find/defs.h: impl_pred_exec is no longer static in pred.c,
