Fix: genetic engineers dropping Schroedinger's cat box.

Only quantum mechanics are supposed to have a chance of death-dropping the
Schroedinger's cat box.

Slash'Em already had this but it was missed when Genetic engineers were ported
over.

doc/fixes37.0

@@ -412,6 +412,7 @@ options help ('? g') listed all boolean options, then repeated them among
 	but for other sprintf implementations they might cause a crash
 change name of #wizlevelflip to #wizfliplevel
 dwarves could sometimes pass through walls without digging their way
+fix genetic engineers dropping Schroedinger's cat box
 
 curses: 'msg_window' option wasn't functional for curses unless the binary
 	also included tty support

src/makemon.c

@@ -755,7 +755,7 @@ register struct monst *mtmp;
             (void) mongets(mtmp, MUMMY_WRAPPING);
         break;
     case S_QUANTMECH:
-        if (!rn2(20)) {
+        if (!rn2(20) && ptr == &mons[PM_QUANTUM_MECHANIC]) {
             struct obj *catcorpse;
 
             otmp = mksobj(LARGE_BOX, FALSE, FALSE);