Revert "gpu: ion: repurpose flags field for heap_mask and caching"

This reverts commit 58415d76e91dd6961e45ed988acafe48d49e1b24.
Revert "gpu: ion: move msm-specific ioctls to custom_ioctl"

This reverts commit bd49e22696c473aa4d51c9931d4aad43ce85760a.
Revert "msm: ion: Only return Ion flags in ion_handle_get_flags"

This reverts commit f5e845fcc2a90b370e5996c019c22fafae0b86d8.
ION: add header files to fix the build
board-spade: Disable ION camera heap. Enable PMEM ADSP heap

Partially bring back PMEM heap (for camera & vidc). Need to disable ION for
vidc too.

Based on https://github.com/Blefish/android_kernel_huawei_u8800/commit/b14f2f2ff6a5ce01e8693522015fcc864266c826
board-spade: Fix video & camcorder
regen defconfig
defconfig: enable ion