complibs: better deduce whether to backup complibs or not

To decide whether we need to backup the companion libraries,
do not rely on the !shared case. In the future other cases
may require not to save the companion libraries (eg. if using
the ones provided by the host distro).

Signed-off-by: "Yann E. MORIN" <yann.morin.1998@anciens.enib.fr>

--- gcc-4.2.0.orig/libstdc++-v3/include/c_std/std_cstdio.h	2006-12-07 10:33:51.000000000 +0100

+++ gcc-4.2.0/libstdc++-v3/include/c_std/std_cstdio.h	2007-05-20 01:05:38.000000000 +0200

@@ -144,7 +144,7 @@

 _GLIBCXX_END_NAMESPACE

-#if _GLIBCXX_USE_C99

+#if _GLIBCXX_USE_C99 || defined(__UCLIBC__)

 #undef snprintf

 #undef vfscanf