phy: samsung-ufs: move phy-exynos7-ufs header

phy: samsung-ufs: move phy-exynos7-ufs header

Instead of using exynos7 ufs definition in phy-exynos7-ufs.h, we should
put it into phy-exynos7-ufs.c to be included different objects or units.

Suggested-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
Link: https://lore.kernel.org/r/20210709094524.110193-2-chanho61.park@samsung.com
Signed-off-by: Vinod Koul <vkoul@kernel.org>