ANDROID: Block: Add OEM data to struct blkcg and struct blkcg_gq

Add ANDROID_OEM_DATA to struct blkcg and struct blkcg_gq, which is
used to implement OEM's blkcg weight. TEach system task has different
importance and priority. Generally, foreground applications and VIP
applications require more I/O bandwidth and lower I/O latency. Therefore, it
is necessary to add OEM-defined weights in blkcg to quickly process
high-priority tasks.

Bug: 337973184
Change-Id: Idd6286235a9ff99feef746d713e09ce2093fa904
Signed-off-by: Dezhi Huang <huangdezhi@hihonor.com>