debug/ltrace: pump ltrace to version 0.7.3

pump ltrace to version 0.7.3
backport a patch from Peter Wu to silence warnings/errors in ltrace

Signed-off-by: '"Peter Wu" <lekensteyn@gmail.com>'
Signed-off-by: '"Daniel Zimmermann" <netzimme@gmail.com>'
[yann.morin.1998@free.fr: remove superfluous empty lines]
Signed-off-by: "Yann E. MORIN" <yann.morin.1998@free.fr>
Message-Id: <8349c35b506aa79c4e69.1392845765@haus-VirtualBox>
Patchwork-Id: 322017

diff -durN gcc-4.4.4.orig/libstdc++-v3/include/c_global/cstdio gcc-4.4.4/libstdc++-v3/include/c_global/cstdio

--- gcc-4.4.4.orig/libstdc++-v3/include/c_global/cstdio	2009-04-10 01:23:07.000000000 +0200

+++ gcc-4.4.4/libstdc++-v3/include/c_global/cstdio	2010-05-16 19:37:06.000000000 +0200

@@ -139,7 +139,7 @@

 _GLIBCXX_END_NAMESPACE

-#if _GLIBCXX_USE_C99

+#if _GLIBCXX_USE_C99 || defined __UCLIBC__

 #undef snprintf

 #undef vfscanf