Force Turkish locales back to C/POSIX; bz#2643

Turkish locales are unique in their handling of the letters 'i' and
'I' (yes, they are different letters) and OpenSSH isn't remotely
prepared to deal with that. For now, the best we can do is to force
OpenSSH to use the C/POSIX locale and try to preserve the UTF-8
encoding if possible.

ok dtucker@
diff --git a/ssh.c b/ssh.c
index 8aa8daa..ee0b16d 100644
--- a/ssh.c
+++ b/ssh.c
@@ -109,6 +109,7 @@
 #include "version.h"
 #include "ssherr.h"
 #include "myproposal.h"
+#include "utf8.h"
 
 #ifdef ENABLE_PKCS11
 #include "ssh-pkcs11.h"
@@ -589,7 +590,7 @@
 	 */
 	umask(022);
 
-	setlocale(LC_CTYPE, "");
+	msetlocale();
 
 	/*
 	 * Initialize option structure to indicate that no values have been