MAINTAINERS: update WOLFSON MICROELECTRONICS

Integrate P:/M: lines
Remove L: linux-kernel@vger.kernel.org

Signed-off-by: Joe Perches <joe@perches.com>
Cc: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>