Revert "libgralloc: Rename USE_PMEM_ADSP to USE_PMEM_CAMERA"

This reverts commit f03363033e97c55d856cee9e2193dcbfd00d7ae1.
Revert "Add missing pieces for PRIV_FLAGS_USES_PMEM_SMI flag"

This reverts commit 1c8312ca5f80fff6e8bf892c709cc5f5e3101381.
Revert "libgralloc: Add back support for PMEM SMI"

This reverts commit 4658e161e82a74b6e759fe2ee3f24dba671f20bc.