gma500: handle poulsbo cursor restriction

Poulsbo needs a physical address in the cursor base register. We allocate a
stolen memory buffer and copy the cursor image provided by userspace into it.
When/If we get our own userspace driver we can map this stolen memory directly.
The patch also adds a mark in chip ops so we can identify devices that has this
requirement.

Signed-off-by: Patrik Jakobsson <patrik.r.jakobsson@gmail.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

drivers/gpu/drm/gma500/cdv_device.c

@@ -563,6 +563,7 @@ const struct psb_ops cdv_chip_ops = {
 	.crtcs = 2,
 	.hdmi_mask = (1 << 0) | (1 << 1),
 	.lvds_mask = (1 << 1),
+	.cursor_needs_phys = 0,
 	.sgx_offset = MRST_SGX_OFFSET,
 	.chip_setup = cdv_chip_setup,
 	.errata = cdv_errata,