ARM: fix Kconfig warning for HAVE_BPF_JIT

Last night's randconfig and the allnoconfig builds spat out the
following warning while building:

warning: (ARM) selects HAVE_BPF_JIT which has unmet direct dependencies (NET)

Acked-by: Mircea Gherzan <mgherzan@gmail.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>