Rename liblttng-ust-libc to liblttng-ust-libc-wrapper

What a beautiful piece of code we can find in python:

/usr/lib/python2.6/ctypes/util.py:

    def _findLib_gcc(name):
        expr = r'[^\(\)\s]*lib%s\.[^\(\)\s]*' % re.escape(name)

Basically, this match any library having "libc.so" in its name. It
should be reported to python developers as a bug, but let's not be the
first to trigger the issue in the wild.

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>