[ARM] Remove bogus gettimeoffset ptr from machine_desc struct.

This was accidently added during the timer code cleanup.
Signed-off-by: Deepak Saxena <dsaxena@plexity.net>

include/asm-arm/mach/arch.h

@@ -46,7 +46,6 @@ struct machine_desc {
 	void			(*map_io)(void);/* IO mapping function	*/
 	void			(*init_irq)(void);
 	void			(*init_time)(void);
-	void			(*gettimeoffset)(void);
 	void			(*init_machine)(void);
 };