This patch fixes a few issues with piglet on Cygwin/X (which uses Mesa
for OpenGL):

1) Cygwin requires that all dependencies be explicitly passed in
dependency order during linking.  This means that static libraries must
precede the shared libraries on which they depend.

2) Cygwin defines log2 as a macro instead of a function.

3) Cygwin doesn't provide lspci(8).