regulator: lp3971 - fix driver link error when built-in.

lp3971_i2c_remove' referenced in section `.data' of drivers/built-in.o:
defined in discarded section `.devexit.text' of drivers/built-in.o

Signed-off-by: Liam Girdwood <lrg@slimlogic.co.uk>
1 file changed