fix steed-in-trap message grammar when hallucinating

Fix the recently reported bug about the wording of trap messsages
when hero's steed has a name but hallucination prevents that name from
being used, yielding "You lead poor wombat into a pit!" and the like.

     I accidentally deleted the message so can't reply to the sender.

[Before applying this patch, take a look at the POLY_TRAP case of the
switch statement in steedintrap().  A misplaced brace has drawn the
default case into one of its `if' statements.  Evidently it's valid C
syntax, but someone among us must have access to a compiler or lint
checking tool which is capable to diagnosing such things.]

doc/fixes34.4

@@ -10,6 +10,8 @@ don't #sit on an object in a pit if you're only on the precipice
 fix message when pushing a boulder into a pool while riding
 when you're teetering on the edge of a pit you can use '>' to enter the pit
 plural of "Nazgul" is "Nazgul" not "Nazguls"
+trap messages referring to named steed were ackwardly worded when hallucination
+	overrode use of the name
 
 
 Platform- and/or Interface-Specific Fixes