Fix indenting on the bswap32 autoconf macro.
Fix indenting on the bswap32 autoconf macro.

We generally prefer spaces to tabs.

Signed-off-by: Erik de Castro Lopo <1586a8e151fb6d548e7a343b9bcdfea42e83ffc0@mega-nerd.com>

waitman/flac,waitman/flac,waitman/flac,waitman/flac,waitman/flac