javacomp: fix handle leak

[Bruno Haible]

The first fallout of the recent Coverity scan:


2017-05-16  Bruno Haible  <br...@clisp.org>

        javacomp: Fix handle leak.
        Found by Coverity.
        * lib/javacomp.c (get_classfile_version): Close fd before returning.

diff --git a/lib/javacomp.c b/lib/javacomp.c
index fe15b2c..3d7d457 100644
--- a/lib/javacomp.c
+++ b/lib/javacomp.c
@@ -525,7 +525,10 @@ get_classfile_version (const char *compiled_file_name)
           /* Verify the class file signature.  */
           if (header[0] == 0xCA && header[1] == 0xFE
               && header[2] == 0xBA && header[3] == 0xBE)
-            return header[7];
+            {
+              close (fd);
+              return header[7];
+            }
         }
       close (fd);
     }