[LyX/master] Fixup 27eb415d: do not define mymkdir() when it is not used.

[Jean-Marc Lasgouttes]

commit 706c9f2aa50558ca0acffb392f85cd278a8a7adc
Author: Jean-Marc Lasgouttes <lasgout...@lyx.org>
Date:   Fri Jan 12 12:22:28 2018 +0100

    Fixup 27eb415d: do not define mymkdir() when it is not used.
    
    Pleases coverity.
---
 src/support/FileName.cpp |    5 ++---
 1 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/src/support/FileName.cpp b/src/support/FileName.cpp
index f9a6f7e..219a9e5 100644
--- a/src/support/FileName.cpp
+++ b/src/support/FileName.cpp
@@ -664,6 +664,7 @@ bool FileName::destroyDirectory() const
 
 
 // Only used in non Win32 platforms
+#ifndef Q_OS_WIN32
 static int mymkdir(char const * pathname, unsigned long int mode)
 {
        // FIXME: why don't we have mode_t in lyx::mkdir prototype ??
@@ -686,10 +687,8 @@ static int mymkdir(char const * pathname, unsigned long 
int mode)
 #else
 #   error "Don't know how to create a directory on this system."
 #endif
-       // squash warnings
-       (void) mode;
-       (void) pathname;
 }
+#endif
 
 
 bool FileName::createDirectory(int permission) const