[media] msi3101: Kconfig select VIDEOBUF2_VMALLOC

[linuxtv-media:master 395/499] sdr-msi3101.c:undefined reference to
`vb2_vmalloc_memops'

Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>