Unsuccessful tripbomb placement consumes ammo

Original behavior verified with DOSBox Duke 1.5.

This is a bug that dates back at least 20 years (tested also with a version of eduke32 from 2004), and appears to be unique to eduke32. It does not occur in JFDuke3D or Raze, the latter of which is based on eduke 2.0.

When the player attempts to place a tripbomb, but is unsuccessful in doing so (e.g. because the surface that it was supposed to be placed on moved away in the meantime, like with a swinging door) then in DOS Duke3D, no ammo is subtracted if the tripbomb sprite is not spawned.

In eduke32 however, the ammo counter always decrements when the tripbomb animation plays, even if the tripbomb sprite is not successfully spawned.

This is most easily reproduced in E1L2 with the swinging bookcase, as well as the door to the bathroom. Attempting to place a tripbomb while the sector is moving can cause the placement to fail, and the problem to be observed.