gma500: Convert spaces to tabs in accel_2d.c.

Convert the spaces within the accel_2d.c file to tabs in order to comply
with the coding style of the kernel.
Signed-off-by: NAkshay Joshi <me@akshayjoshi.com>
Signed-off-by: NAlan Cox <alan@linux.intel.com>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>