MA-14916-4 [iot] Update size format for write_counter

MA-14916-4 [iot] Update size format for write_counter

This commit is cherry-picked from community:
	commit 343749c42554b058e53086aefe21d47b383326d5
	author Kever Yang <kever.yang@rock-chips.com>
	date Wed, 19 Jul 2017 18:13:59 +0800 (19:13 +0900)

	mmc: rpmb: update size format for write_counter

	According to MMC spec, the write_counter is 4-byte length,
	use 'int' instead of 'long' type for the 'long' is not 4-byte
	in 64 bit CPU.

	Signed-off-by: Jason Zhu <jason.zhu@rock-chips.com>
	Signed-off-by: Kever Yang <kever.yang@rock-chips.com>
	Reviewed-by: Simon Glass <sjg@chromium.org>
	Signed-off-by: Jaehoon Chung <jh80.chung@samsung.com>
Test: Access RPMB successfully on imx8m.

Change-Id: I402b53c990856c2cdf7c3686eabf259f5581464d
Signed-off-by: Luo Ji <ji.luo@nxp.com>