reset: ti-syscon: fix to_ti_syscon_reset_data macro

The to_ti_syscon_reset_data macro currently only works if the
parameter passed into it is called 'rcdev'.

Fixes a checkpatch --strict issue:

  CHECK: Macro argument reuse 'rcdev' - possible side-effects?
  #53: FILE: drivers/reset/reset-ti-syscon.c:53:
  +#define to_ti_syscon_reset_data(rcdev)	\
  +	container_of(rcdev, struct ti_syscon_reset_data, rcdev)

Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>