Following on from the removal of the automatic "is there a script to run" logic,

more speedups for building packages.

Get rid of a .USE macro, and do not spawn sub-makes for the pre-, do- and
post-target stages, replacing them with standard make(1) targets.

Timing information as follows (multiple runs performed, best results taken):

800 MHz Celeron, 128 MB, local pkgsrc, local obj
scripts/, pre,do,post-*:  	0.731u 0.261s 0:02.04 48.5%     0+0k 29+168io 9pf+0w
no scripts/, pre,do,post-*:	0.678u 0.242s 0:01.30 70.0%     0+0k 0+169io 0pf+0w
no scripts/, no pre,do,post-*:	0.267u 0.089s 0:00.90 37.7%     0+0k 0+155io 0pf+0w

40 MHz Sparc, 36 MB, nfs pkgsrc, local obj
scripts/, pre,do,post-*:  	22.590u 6.839s 0:33.31 88.3%    0+0k 121+254io 0pf+0w
no scripts/, pre,do,post-*:	22.481u 6.442s 0:33.30 86.8%    0+0k 120+251io 0pf+0w
no scripts/, no pre,do,post-*:   8.534u 4.189s 0:16.48 77.1%    0+0k 105+242io 0pf+0w

0 files changed, 0 insertions, 0 deletions