MAINTAINERS: better list for "POSIX CLOCKS and TIMERS"

POSIX CLOCKS and TIMERS disscussion is more appropriate
on linux-kernel than linux-net. As suggested by the maintainer,
George Anzinger.

Signed-off-by: Horms <[e-mail]>
Acked-by: George Anzinger <[e-mail]>
Signed-off-by: Adrian Bunk <[e-mail]>

MAINTAINERS

···
 POSIX CLOCKS and TIMERS
 P:	George Anzinger
 M:	[e-mail]
-L:	[e-mail]
+L:	[e-mail]
 S:	Supported
 
 POWERPC 4xx EMAC DRIVER