minigbm: refactor and rename mapping struct

Since some drivers (AMDGPU, Tegra) may have to do expensive tiling
and detiling operations, we should try to take advantage of the
access regions passed in by gralloc and gbm. Let's refactor struct
map_data so we can separate the actual mapping and access region.

Here is the Coccinelle rule used in this change:

@@ struct map_info *M; @@
-   (M)
+   M->vma

In addition, struct map_data was also renamed to struct mapping.

BUG=chromium:764871
TEST= mmap_test -g on Kevin

Change-Id: Idb094aa3b5f81e45ce3a2f4fb2d9bf8fba32bf29
Reviewed-on: https://chromium-review.googlesource.com/758144
Commit-Ready: Gurchetan Singh <gurchetansingh@chromium.org>
Tested-by: Gurchetan Singh <gurchetansingh@chromium.org>
Reviewed-by: Joe Kniss <djmk@google.com>
Reviewed-by: Stéphane Marchesin <marcheu@chromium.org>
diff --git a/helpers.h b/helpers.h
index 0e3fd14..cbd8f18 100644
--- a/helpers.h
+++ b/helpers.h
@@ -17,9 +17,9 @@
 int drv_dumb_bo_destroy(struct bo *bo);
 int drv_gem_bo_destroy(struct bo *bo);
 int drv_prime_bo_import(struct bo *bo, struct drv_import_fd_data *data);
-void *drv_dumb_bo_map(struct bo *bo, struct map_info *data, size_t plane, uint32_t map_flags);
-int drv_bo_munmap(struct bo *bo, struct map_info *data);
-int drv_map_info_destroy(struct bo *bo);
+void *drv_dumb_bo_map(struct bo *bo, struct mapping *mapping, size_t plane, uint32_t map_flags);
+int drv_bo_munmap(struct bo *bo, struct mapping *mapping);
+int drv_mapping_destroy(struct bo *bo);
 int drv_get_prot(uint32_t map_flags);
 uintptr_t drv_get_reference_count(struct driver *drv, struct bo *bo, size_t plane);
 void drv_increment_reference_count(struct driver *drv, struct bo *bo, size_t plane);