Migrating pkg-config checks for libusb

[Markus Dolze]

Hello,

I have a port (sysutils/lcdproc) using pkg-config to check for the
presence and flags of libusb. While this works fine for FreeBSD up to
7.2, it does not work for 8-current.

Instead of fixing it in the ports I am looking for a way to detect the
availability of libusb properly in the original source. Any ideas how to
do this? Some autotools M4/shell code is appreciated.

Regards,
Markus