staging: dwc2: toggle periodic debugging output separately

This adds a config option USB_DWC2_DEBUG_PERIODIC that allows debugging
output be suppressed for periodic transfers. This helps when debugging
non-periodic transfers while there are also periodic transfers going on
(both to make the debug output less polluted and to prevent all CPU time
going to debug messages).

In addition, a debug message from dwc2_hcd_is_status_changed is removed
entirely, since it often floods the log regardless of periodic
transfers.

Signed-off-by: Matthijs Kooijman <matthijs@stdin.nl>
Cc: Paul Zimmerman <Paul.Zimmerman@synopsys.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/dwc2/Kconfig

@@ -39,4 +39,14 @@ config USB_DWC2_TRACK_MISSED_SOFS
 	  Say Y here to enable logging of missed SOF events to the dmesg log.
 	  If in doubt, say N.
 
+config USB_DWC2_DEBUG_PERIODIC
+	bool "Enable Debugging Messages For Periodic Transfers"
+	depends on USB_DWC2_DEBUG || USB_DWC2_VERBOSE
+	default y
+	help
+	  Say N here to disable (verbose) debugging messages to be
+	  logged for periodic transfers. This allows better debugging of
+	  non-periodic transfers, but of course the debug logs will be
+	  incomplete. Note that this also disables some debug messages
+	  for which the transfer type cannot be deduced.
 endif