libhdfs compilation error with fresh checkout

[Kirk True]

Hi all,

With a fresh checkout, running `ant binary` generates this error:
   create-libhdfs-configure:
        [mkdir] Created dir: /tmp/test/hadoop-hdfs/src/c++/libhdfs/config
         [exec] configure.ac:116: error: possibly undefined macro:
   AC_PROG_LIBTOOL
         [exec]       If this token and others are legitimate, please
   use m4_pattern_allow.
         [exec]       See the Autoconf documentation.
         [exec] autoreconf: /usr/bin/autoconf failed with exit status: 1

   BUILD FAILED
   /tmp/test/hadoop-hdfs/build.xml:1488: The following error occurred
   while executing this line:
   /tmp/test/hadoop-hdfs/build.xml:1475: exec returned: 1


This seems to be a result of HDFS-2022 from last week, though I'm sure 
it's something not set up correctly in my environment.

Thanks,
Kirk