drm/exynos: Fix a fake mmap offset creation
drm/exynos: Fix a fake mmap offset creation

Make a fake mmap offset only when it needs.

Signed-off-by: Joonyoung Shim <b2207686f8c5343cf0f505ae1d5720ecb0c3202a@samsung.com>
Signed-off-by: Inki Dae <bae4a7a27bbc965064e97edd6e179ac4979db440@samsung.com>
Signed-off-by: Kyungmin Park <504c23c4986a3760712724894be3105092c27331@samsung.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas,TeamVee-Kanas/android_kernel_samsung_kanas