backlight: 88pm860x_bl: remove an unnecessary line continuation

Remove an unnecessary line continuation in pm860x_backlight_probe().
Also, a checkpatch warning is fixed as below:

  WARNING: Avoid unnecessary line continuations

[akpm@linux-foundation.org: remove newline]
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>