Fix typo of --oat-fd description in help

--oat-fd description in help was copied from --oat-file description.

Change-Id: Idbf36018af58db169f6d65382a7602ec950cce99
Signed-off-by: Wonil Kim <wonil.kim@gmail.com>
diff --git a/dex2oat/dex2oat.cc b/dex2oat/dex2oat.cc
index ac76c35..c70db14 100644
--- a/dex2oat/dex2oat.cc
+++ b/dex2oat/dex2oat.cc
@@ -110,7 +110,7 @@
   UsageError("      Example: --oat-file=/system/framework/boot.oat");
   UsageError("");
   UsageError("  --oat-fd=<number>: specifies the oat output destination via a file descriptor.");
-  UsageError("      Example: --oat-file=/system/framework/boot.oat");
+  UsageError("      Example: --oat-fd=6");
   UsageError("");
   UsageError("  --oat-location=<oat-name>: specifies a symbolic name for the file corresponding");
   UsageError("      to the file descriptor specified by --oat-fd.");