drm/exynos: dsi: use IS_ERR() to check devm_ioremap_resource() results
drm/exynos: dsi: use IS_ERR() to check devm_ioremap_resource() results

devm_ioremap_resource() returns an error pointer, not NULL. Thus,
the result should be checked with IS_ERR().

Signed-off-by: Jingoo Han <fc379137a64feb86ce38ec5811a14280acc1ccfc@samsung.com>
Signed-off-by: Inki Dae <bae4a7a27bbc965064e97edd6e179ac4979db440@samsung.com>
Signed-off-by: Dave Airlie <f2295d84e358395675bc8031be58672073ae065e@redhat.com>

KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs,KristFoundation/Programs