camera: Fix compiler warnings.

Cleanup to avoid too many type casting where not needed, adjust indentation.
bt-vendor: Add epilog op.
u8800: Use number width instead of precision width on format.
u8800: Fix typos.
u8800: Fix libril compile error.

Missed this in the first patch.
sensors: Update light sensor settings only on success.

There is a possibility the driver might fail writing new settings, either due to
the I/O error or file open issues. Bail out properly on such cases.