Documentation: fix usb related doc refs

Update ref to usb proc_usb_info.txt.
Signed-off-by: Tom Saeger <tom.saeger@oracle.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>

Documentation/driver-api/usb/usb.rst

@@ -690,9 +690,7 @@ The USB devices are now exported via debugfs:
 This file is handy for status viewing tools in user mode, which can scan
 the text format and ignore most of it. More detailed device status
 (including class and vendor status) is available from device-specific
-files. For information about the current format of this file, see the
-``Documentation/usb/proc_usb_info.txt`` file in your Linux kernel
-sources.
+files. For information about the current format of this file, see below.
 
 This file, in combination with the poll() system call, can also be used
 to detect when devices are added or removed::

Documentation/networking/cdc_mbim.txt

@@ -332,8 +332,8 @@ References
 [5] "MBIM (Mobile Broadband Interface Model) Registry"
        - http://compliance.usb.org/mbim/
 
-[6] "/dev/bus/usb filesystem output"
-       - Documentation/usb/proc_usb_info.txt
+[6] "/sys/kernel/debug/usb/devices output format"
+       - Documentation/driver-api/usb/usb.rst
 
 [7] "/sys/bus/usb/devices/.../descriptors"
        - Documentation/ABI/stable/sysfs-bus-usb

Documentation/usb/gadget-testing.txt

@@ -773,7 +773,7 @@ host:
 # cat /dev/usb/lp0
 
 More advanced testing can be done with the prn_example
-described in Documentation/usb/gadget-printer.txt.
+described in Documentation/usb/gadget_printer.txt.
 
 
 20. UAC1 function (virtual ALSA card, using u_audio API)