Reported for applying a figurine that was used up, but I found the same
problem could affect cursed bells and candles. Modified all three helper
functions to indicate when the object is gone, and modified doapply to
deal with this before doing the artifact check.
<Someone> noticed that if one builds something in util and the required .o
files aren't already built in src, the .o gets placed in the wrong place.
Added the missing '-o $@' to the compilation command.
Reported on RH 7.2 and 8.0. Compilation failed because system headers that
needed _GNU_SOURCE on these Redhat versions got included before it was
defined. To ensure _GNU_SOURCE is defined, added an autodetect for it to
config1.h and removed the need to set it in unixres.c. __linux__ is also
checked elsewhere.
As reported, if you're twoweaponing and die, your secondary weapon may
become cursed and drop. But, the bones file code is dropping everything
and tries to drop it again, causing a panic. drop_upon_death just clears
things out, so follow suit for uswapwep.
