extcon: fix switch class porting guide (Documentation)
extcon: fix switch class porting guide (Documentation)

- Unfinished sentence finished.
- Incorrect description on the compat-mode condition corrected.

Signed-off-by: MyungJoo Ham <84146178f7c201fa3079bfc93fccba71d81dffe3@samsung.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs