linux warning bits (trunk only)

a few syntactical tweaks to silence warnings from gcc on linux
for code that was only updated in the trunk

src/cmd.c

@@ -1094,7 +1094,7 @@ char resultbuf[];	/* should be at least [7] to hold "18/100\0" */
 	    Sprintf(resultbuf, "%d", attrval);
 	else if (attrval > STR18(100))	/* 19 to 25 */
 	    Sprintf(resultbuf, "%d", attrval - 100);
-	else	/* simplify "18/**" to be "18/100" */
+	else	/* simplify "18/ **" to be "18/100" */
 	    Sprintf(resultbuf, "18/%02d", attrval - 18);
 	return resultbuf;
 }

src/hack.c

@@ -1105,7 +1105,7 @@ struct trap *desttrap;	/* nonnull if another trap at <x,y> */
 	    }
 	    break;
     default:
-	    impossible("trapmove: stuck in unknown trap? (%s)", u.utraptype);
+	    impossible("trapmove: stuck in unknown trap? (%d)", (int)u.utraptype);
 	    break;
     }
     return FALSE;

src/hacklib.c

@@ -662,7 +662,7 @@ time_t date;
 	    datenum = (long)lt->tm_year + 2000L;
 	else
 	    datenum = (long)lt->tm_year + 1900L;
-	Sprintf(datestr, "%04d%02d%02d%02d%02d%02d",
+	Sprintf(datestr, "%04ld%02d%02d%02d%02d%02d",
 		datenum, lt->tm_mon + 1, lt->tm_mday,
 		lt->tm_hour, lt->tm_min, lt->tm_sec);
 	return(datestr);