Analyse following RPM build log snippet. Describe contents accurately, without speculation or suggestions for resolution.            
Your analysis must be as concise as possible, while keeping relevant information intact.
Snippet: 
checking for libusb-config... no
checking for usb_init in -lusb... no
configure: error: Unable to find libusb
RPM build errors:
error: Bad exit status from /var/tmp/rpm-tmp.3Se0cU (%build)
    Bad exit status from /var/tmp/rpm-tmp.3Se0cU (%build)
The configure script complains about missing libusb dependency.