windfarm: remove three exported but unused functions

wf_find_control(), wf_find_sensor(), and wf_is_overtemp() are exported
but unused. Remove these three functions.

Signed-off-by: Paul Bolle <pebolle@tiscali.nl>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>

path: root/Extra

# Targets that need extra treatment for now

curvetun: LDFLAGS += -L ${CONFIG_NACL_LIB_DIR}
mausezahn: CFLAGS = $(mausezahn-eflags)