Bug#534512: regression: pieces have lost borders and become transparent

[h.g. muller]

Note that xboard supports two kind of piece symbols; monochrome bitmaps,
(as seen in "xboard-broken") and pixmaps with outline borders (as seen in
"xboard-fine"). Depending on a compile-time switch set by the configuration
process on the presence of the XPM library, one or the other are used for
the built-in symbols.

For some reason the xboard binary in this package has been compiled in
absence of LIBXPM, unlike the binary included in the 4.2.7 packages.
As a result, you get the (inferior) bitmaps as built-ins.

The period at the beginning of the bitmap file names is a genuine bug;
XBoard fails to create the proper name for bitmaps of pieces that are not
participating in the variant that is selected at startup. It was already
fixed in 4.4.0~alpha-7 and later.

H.G. Muller, upstream developer of XBoard.