[configure] Fixup breakage with recent autoconf

To avoid possibly undefined macro: LT_CURRENT, LT_REVISION and LT_AGE according to http://cgit.freedesktop.org/cairo/commit/?h=1.6&id=e13586b6b78d3636c3e00b437fdb4f3ac449b185
Merge pull request #10 from sbob84/patch-1

[configure] Fixup breakage with recent autoconf