Version the build-depends on liblz4-dev to >= 0.0~r126

We need r126 of lz4, as this introduces the lz4frame.h
header.

debian/control

@@ -7,7 +7,7 @@ Uploaders: Michael Vogt <mvo@debian.org>,
 Standards-Version: 3.9.6
 Build-Depends: dpkg-dev (>= 1.17.14), debhelper (>= 9.20141010), libdb-dev,
  gettext (>= 0.12), libcurl4-gnutls-dev (>= 7.19.4~),
- zlib1g-dev, libbz2-dev, liblzma-dev, liblz4-dev,
+ zlib1g-dev, libbz2-dev, liblzma-dev, liblz4-dev (>= 0.0~r126),
  xsltproc, docbook-xsl, docbook-xml, po4a (>= 0.34-2),
  autotools-dev, autoconf, automake, libgtest-dev <!nocheck>,
  g++ (>= 4:5.2)