package/qemu: fix build of host-qemu on systems with old kernel headers

package/qemu: fix build of host-qemu on systems with old kernel headers

Qemu assumes that when <linux/usbdevice_fs.h> is available, it can
build its USBFS code. However, some systems have
<linux/usbdevice_fs.h>, but it doesn't provide all the definitions
that Qemu needs, causing a build failure.

In order to fix this, we introduce a Qemu patch that improves the
check that determines whether USBFS support should be enabled or not.

Fixes:

  http://autobuild.buildroot.net/results/c4af5505f80e1e6185df70d191e85d9393df5795/

Signed-off-by: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Signed-off-by: Peter Korsgaard <peter@korsgaard.com>