Fix find_panel() (again)

This fixes a not-so-subtle bug introduced by 289c8a77.

libcrystfel/src/detector.c

@@ -426,9 +426,9 @@ struct panel *find_panel(struct detector *det, double fs, double ss)
 
 	for ( p=0; p<det->n_panels; p++ ) {
 		if ( (fs >= det->panels[p].min_fs)
-		  && (fs <= det->panels[p].max_fs+1)
+		  && (fs < det->panels[p].max_fs+1)
 		  && (ss >= det->panels[p].min_ss)
-		  && (ss <= det->panels[p].max_ss+1) ) {
+		  && (ss < det->panels[p].max_ss+1) ) {
 			return &det->panels[p];
 		}
 	}