Follow-up fix for r737173 (patch 46544) - filename arg was not properly parsed.

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@737238 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/poi/hssf/extractor/ExcelExtractor.java

@@ -89,7 +89,7 @@ public class ExcelExtractor extends POIOLE2TextExtractor implements org.apache.p
 					break;
 				}
 				if ("-i".equals(arg)) {
-					i++; // step to next arg
+					arg = args[++i]; // step to next arg
 					if (i >= nArgs) {
 						throw new CommandParseException("Expected filename after '-i'");
 					}