darwin: downgrade error message on failure to open interface to info

This resolves an issue introduced by the implementation of the kernel detach code. This
code used claim_interface to detect if a kernel driver is attached. The issue is that if
a driver is attached or the interface is not available and an error message was printed
out. Since this is not an error the info level is more appropriate.

Also downgrading a number of warnings to clean up the output.

Closes #955

Signed-off-by: Nathan Hjelm <hjelmn@google.com>

libusb/os/darwin_usb.c

diff --git a/libusb/os/darwin_usb.c b/libusb/os/darwin_usb.c
index 93bf05c..d0180e4 100644
--- a/libusb/os/darwin_usb.c
+++ b/libusb/os/darwin_usb.c
@@ -1467,7 +1467,7 @@
   }
 
   if (!usbInterface) {
-    usbi_err (HANDLE_CTX (dev_handle), "interface not found");
+    usbi_info (HANDLE_CTX (dev_handle), "interface not found");
     return LIBUSB_ERROR_NOT_FOUND;
   }
 
@@ -1503,7 +1503,7 @@
   /* claim the interface */
   kresult = (*(cInterface->interface))->USBInterfaceOpen(cInterface->interface);
   if (kresult != kIOReturnSuccess) {
-    usbi_err (HANDLE_CTX (dev_handle), "USBInterfaceOpen: %s", darwin_error_str(kresult));
+    usbi_info (HANDLE_CTX (dev_handle), "USBInterfaceOpen: %s", darwin_error_str(kresult));
     return darwin_to_libusb (kresult);
   }
 
@@ -2387,14 +2387,14 @@
     usbi_dbg ("attempting to detach kernel driver from device");
 
     if (!darwin_has_capture_entitlements ()) {
-      usbi_warn (HANDLE_CTX (dev_handle), "no capture entitlements. can not detach the kernel driver for this device");
+      usbi_info (HANDLE_CTX (dev_handle), "no capture entitlements. can not detach the kernel driver for this device");
       return LIBUSB_ERROR_NOT_SUPPORTED;
     }
 
     /* request authorization */
     kresult = IOServiceAuthorize (dpriv->service, kIOServiceInteractionAllowed);
     if (kresult != kIOReturnSuccess) {
-      usbi_err (HANDLE_CTX (dev_handle), "IOServiceAuthorize: %s", darwin_error_str(kresult));
+      usbi_warn (HANDLE_CTX (dev_handle), "IOServiceAuthorize: %s", darwin_error_str(kresult));
       return darwin_to_libusb (kresult);
     }
 
@@ -2440,7 +2440,7 @@
   if (dev_handle->auto_detach_kernel_driver) {
     ret = darwin_detach_kernel_driver (dev_handle, iface);
     if (ret != LIBUSB_SUCCESS) {
-      usbi_warn (HANDLE_CTX (dev_handle), "failed to auto-detach the kernel driver for this device, ret=%d", ret);
+      usbi_info (HANDLE_CTX (dev_handle), "failed to auto-detach the kernel driver for this device, ret=%d", ret);
     }
   }
 
@@ -2459,7 +2459,7 @@
   if (dev_handle->auto_detach_kernel_driver && dpriv->capture_count > 0) {
     ret = darwin_attach_kernel_driver (dev_handle, iface);
     if (LIBUSB_SUCCESS != ret) {
-      usbi_warn (HANDLE_CTX (dev_handle), "on attempt to reattach the kernel driver got ret=%d", ret);
+      usbi_info (HANDLE_CTX (dev_handle), "on attempt to reattach the kernel driver got ret=%d", ret);
     }
     /* ignore the error as the interface was successfully released */
   }

libusb/version_nano.h

diff --git a/libusb/version_nano.h b/libusb/version_nano.h
index 2773f71..4116e1d 100644
--- a/libusb/version_nano.h
+++ b/libusb/version_nano.h
@@ -1 +1 @@
-#define LIBUSB_NANO 11639
+#define LIBUSB_NANO 11640