Fix module compiling:
WARNING: drivers/video/backlight/corgi_bl.o - Section mismatch:
reference to .init.text: from .data between '$d' (at offset 0x0) and
'bl_mutex'
Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Anton Vorontsov <cbou@mail.ru> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>