Currently, we step into drivers/hid/ based on the value of
CONFIG_HID.

However, that value is a tristate, meaning that it can be a module.

As per the documentation, if we jump into the subdirectory by
following an obj-m, we can not compile anything inside that
subdirectory in vmlinux. It is considered as a bug.

To make things more friendly to HID-BPF, split HID (the HID core
parameter) from HID_SUPPORT (do we want any kind of HID support in the
system?), and make this new config a boolean.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>