V4L/DVB (7306): pvrusb2: Fix oops possible when claiming a NULL stream
V4L/DVB (7306): pvrusb2: Fix oops possible when claiming a NULL stream

Signed-off-by: Mike Isely <2ea935d8c40c107fcce175c9ba49ff51e4d69087@pobox.com>
Signed-off-by: Mauro Carvalho Chehab <ad86ba2154032c9f55743a190faa2459a9d61d42@infradead.org>

KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas