Cleanup the zlib exansion test (including compiler warnings).

* subversion/tests/libsvn_subr/checksum.c
  (zlib_expansion_test):  Use types that match zlib's interface instead of
    types that may be different sizes on different platforms.  Calculate the
    CRC as we do the inflate, this avoids an ugly typecast.  Remove a bunch of
    unnecessary typecasts and use the proper format flags.  Avoid pointer
    arithmatic when calculating the size of the remaining input for the last
    inflate() call.


git-svn-id: https://svn.apache.org/repos/asf/subversion/trunk@1569911 13f79535-47bb-0310-9956-ffa450edef68