msm: camera: Fix camera build issue

If CONFIG_FB_MSM is disabled in the msm8994_defconfig,
the camera driver fails to compile with the following
errors. This is happening because the Kconfig option
for the camera driver does not select CONFIG_LED_CLASS
explicitly, but relies on CONFIG_FB_MSM to select it.

CRs-Fixed: 748013
Change-Id: Icbbbcbdab1da20b35ef8d7d326d0d0d470b97d5c
Signed-off-by: Evgeniy Borisov <eborisov@codeaurora.org>