[LyX/master] Remove warning

[Kornel Benko]

commit 5efd59733a019dd1f61510bb43cc7306b546e298
Author: Kornel Benko <kor...@lyx.org>
Date:   Sun Jan 5 10:04:23 2014 +0100

    Remove warning

diff --git a/src/support/filetools.cpp b/src/support/filetools.cpp
index 387045f..0012481 100644
--- a/src/support/filetools.cpp
+++ b/src/support/filetools.cpp
@@ -1077,7 +1077,7 @@ int fileLock(const char * lock_file)
        return(fd);
 }
 
-void fileUnlock(int fd, const char * lock_file)
+void fileUnlock(int fd, const char * /* lock_file*/)
 {
 #if defined(HAVE_LOCKF)
        if ( fd >= 0) {